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Description: B is decreasing. (Contributed by Glauco Siliprandi, 29-Jun-2017)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | stirlinglem11.1 | ⊢ 𝐴 = ( 𝑛 ∈ ℕ ↦ ( ( ! ‘ 𝑛 ) / ( ( √ ‘ ( 2 · 𝑛 ) ) · ( ( 𝑛 / e ) ↑ 𝑛 ) ) ) ) | |
| stirlinglem11.2 | ⊢ 𝐵 = ( 𝑛 ∈ ℕ ↦ ( log ‘ ( 𝐴 ‘ 𝑛 ) ) ) | ||
| stirlinglem11.3 | ⊢ 𝐾 = ( 𝑘 ∈ ℕ ↦ ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) ) | ||
| Assertion | stirlinglem11 | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ ( 𝑁 + 1 ) ) < ( 𝐵 ‘ 𝑁 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | stirlinglem11.1 | ⊢ 𝐴 = ( 𝑛 ∈ ℕ ↦ ( ( ! ‘ 𝑛 ) / ( ( √ ‘ ( 2 · 𝑛 ) ) · ( ( 𝑛 / e ) ↑ 𝑛 ) ) ) ) | |
| 2 | stirlinglem11.2 | ⊢ 𝐵 = ( 𝑛 ∈ ℕ ↦ ( log ‘ ( 𝐴 ‘ 𝑛 ) ) ) | |
| 3 | stirlinglem11.3 | ⊢ 𝐾 = ( 𝑘 ∈ ℕ ↦ ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) ) | |
| 4 | 0red | ⊢ ( 𝑁 ∈ ℕ → 0 ∈ ℝ ) | |
| 5 | 3 | a1i | ⊢ ( 𝑁 ∈ ℕ → 𝐾 = ( 𝑘 ∈ ℕ ↦ ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) ) ) |
| 6 | simpr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑘 = 1 ) → 𝑘 = 1 ) | |
| 7 | 6 | oveq2d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑘 = 1 ) → ( 2 · 𝑘 ) = ( 2 · 1 ) ) |
| 8 | 7 | oveq1d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑘 = 1 ) → ( ( 2 · 𝑘 ) + 1 ) = ( ( 2 · 1 ) + 1 ) ) |
| 9 | 8 | oveq2d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑘 = 1 ) → ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) = ( 1 / ( ( 2 · 1 ) + 1 ) ) ) |
| 10 | 7 | oveq2d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑘 = 1 ) → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) = ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ) |
| 11 | 9 10 | oveq12d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑘 = 1 ) → ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) = ( ( 1 / ( ( 2 · 1 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ) ) |
| 12 | 1nn | ⊢ 1 ∈ ℕ | |
| 13 | 12 | a1i | ⊢ ( 𝑁 ∈ ℕ → 1 ∈ ℕ ) |
| 14 | 2cnd | ⊢ ( 𝑁 ∈ ℕ → 2 ∈ ℂ ) | |
| 15 | 1cnd | ⊢ ( 𝑁 ∈ ℕ → 1 ∈ ℂ ) | |
| 16 | 14 15 | mulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 1 ) ∈ ℂ ) |
| 17 | 16 15 | addcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 1 ) + 1 ) ∈ ℂ ) |
| 18 | 2t1e2 | ⊢ ( 2 · 1 ) = 2 | |
| 19 | 18 | oveq1i | ⊢ ( ( 2 · 1 ) + 1 ) = ( 2 + 1 ) |
| 20 | 2p1e3 | ⊢ ( 2 + 1 ) = 3 | |
| 21 | 19 20 | eqtri | ⊢ ( ( 2 · 1 ) + 1 ) = 3 |
| 22 | 3ne0 | ⊢ 3 ≠ 0 | |
| 23 | 21 22 | eqnetri | ⊢ ( ( 2 · 1 ) + 1 ) ≠ 0 |
| 24 | 23 | a1i | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 1 ) + 1 ) ≠ 0 ) |
| 25 | 17 24 | reccld | ⊢ ( 𝑁 ∈ ℕ → ( 1 / ( ( 2 · 1 ) + 1 ) ) ∈ ℂ ) |
| 26 | nncn | ⊢ ( 𝑁 ∈ ℕ → 𝑁 ∈ ℂ ) | |
| 27 | 14 26 | mulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 𝑁 ) ∈ ℂ ) |
| 28 | 27 15 | addcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 𝑁 ) + 1 ) ∈ ℂ ) |
| 29 | 1red | ⊢ ( 𝑁 ∈ ℕ → 1 ∈ ℝ ) | |
| 30 | 2re | ⊢ 2 ∈ ℝ | |
| 31 | 30 | a1i | ⊢ ( 𝑁 ∈ ℕ → 2 ∈ ℝ ) |
| 32 | nnre | ⊢ ( 𝑁 ∈ ℕ → 𝑁 ∈ ℝ ) | |
| 33 | 31 32 | remulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 𝑁 ) ∈ ℝ ) |
| 34 | 33 29 | readdcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 𝑁 ) + 1 ) ∈ ℝ ) |
| 35 | 0lt1 | ⊢ 0 < 1 | |
| 36 | 35 | a1i | ⊢ ( 𝑁 ∈ ℕ → 0 < 1 ) |
| 37 | 2rp | ⊢ 2 ∈ ℝ+ | |
| 38 | 37 | a1i | ⊢ ( 𝑁 ∈ ℕ → 2 ∈ ℝ+ ) |
| 39 | nnrp | ⊢ ( 𝑁 ∈ ℕ → 𝑁 ∈ ℝ+ ) | |
| 40 | 38 39 | rpmulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 𝑁 ) ∈ ℝ+ ) |
| 41 | 29 40 | ltaddrp2d | ⊢ ( 𝑁 ∈ ℕ → 1 < ( ( 2 · 𝑁 ) + 1 ) ) |
| 42 | 4 29 34 36 41 | lttrd | ⊢ ( 𝑁 ∈ ℕ → 0 < ( ( 2 · 𝑁 ) + 1 ) ) |
| 43 | 42 | gt0ne0d | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 𝑁 ) + 1 ) ≠ 0 ) |
| 44 | 28 43 | reccld | ⊢ ( 𝑁 ∈ ℕ → ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ∈ ℂ ) |
| 45 | 2nn0 | ⊢ 2 ∈ ℕ0 | |
| 46 | 45 | a1i | ⊢ ( 𝑁 ∈ ℕ → 2 ∈ ℕ0 ) |
| 47 | 1nn0 | ⊢ 1 ∈ ℕ0 | |
| 48 | 47 | a1i | ⊢ ( 𝑁 ∈ ℕ → 1 ∈ ℕ0 ) |
| 49 | 46 48 | nn0mulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 1 ) ∈ ℕ0 ) |
| 50 | 44 49 | expcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ∈ ℂ ) |
| 51 | 25 50 | mulcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 1 / ( ( 2 · 1 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ) ∈ ℂ ) |
| 52 | 5 11 13 51 | fvmptd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐾 ‘ 1 ) = ( ( 1 / ( ( 2 · 1 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ) ) |
| 53 | 1re | ⊢ 1 ∈ ℝ | |
| 54 | 30 53 | remulcli | ⊢ ( 2 · 1 ) ∈ ℝ |
| 55 | 54 53 | readdcli | ⊢ ( ( 2 · 1 ) + 1 ) ∈ ℝ |
| 56 | 55 23 | rereccli | ⊢ ( 1 / ( ( 2 · 1 ) + 1 ) ) ∈ ℝ |
| 57 | 56 | a1i | ⊢ ( 𝑁 ∈ ℕ → ( 1 / ( ( 2 · 1 ) + 1 ) ) ∈ ℝ ) |
| 58 | 34 43 | rereccld | ⊢ ( 𝑁 ∈ ℕ → ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ∈ ℝ ) |
| 59 | 58 49 | reexpcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ∈ ℝ ) |
| 60 | 57 59 | remulcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 1 / ( ( 2 · 1 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ) ∈ ℝ ) |
| 61 | 52 60 | eqeltrd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐾 ‘ 1 ) ∈ ℝ ) |
| 62 | 1 | stirlinglem2 | ⊢ ( 𝑁 ∈ ℕ → ( 𝐴 ‘ 𝑁 ) ∈ ℝ+ ) |
| 63 | 62 | relogcld | ⊢ ( 𝑁 ∈ ℕ → ( log ‘ ( 𝐴 ‘ 𝑁 ) ) ∈ ℝ ) |
| 64 | nfcv | ⊢ Ⅎ 𝑛 𝑁 | |
| 65 | nfcv | ⊢ Ⅎ 𝑛 log | |
| 66 | nfmpt1 | ⊢ Ⅎ 𝑛 ( 𝑛 ∈ ℕ ↦ ( ( ! ‘ 𝑛 ) / ( ( √ ‘ ( 2 · 𝑛 ) ) · ( ( 𝑛 / e ) ↑ 𝑛 ) ) ) ) | |
| 67 | 1 66 | nfcxfr | ⊢ Ⅎ 𝑛 𝐴 |
| 68 | 67 64 | nffv | ⊢ Ⅎ 𝑛 ( 𝐴 ‘ 𝑁 ) |
| 69 | 65 68 | nffv | ⊢ Ⅎ 𝑛 ( log ‘ ( 𝐴 ‘ 𝑁 ) ) |
| 70 | 2fveq3 | ⊢ ( 𝑛 = 𝑁 → ( log ‘ ( 𝐴 ‘ 𝑛 ) ) = ( log ‘ ( 𝐴 ‘ 𝑁 ) ) ) | |
| 71 | 64 69 70 2 | fvmptf | ⊢ ( ( 𝑁 ∈ ℕ ∧ ( log ‘ ( 𝐴 ‘ 𝑁 ) ) ∈ ℝ ) → ( 𝐵 ‘ 𝑁 ) = ( log ‘ ( 𝐴 ‘ 𝑁 ) ) ) |
| 72 | 63 71 | mpdan | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ 𝑁 ) = ( log ‘ ( 𝐴 ‘ 𝑁 ) ) ) |
| 73 | 72 63 | eqeltrd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ 𝑁 ) ∈ ℝ ) |
| 74 | peano2nn | ⊢ ( 𝑁 ∈ ℕ → ( 𝑁 + 1 ) ∈ ℕ ) | |
| 75 | 1 | stirlinglem2 | ⊢ ( ( 𝑁 + 1 ) ∈ ℕ → ( 𝐴 ‘ ( 𝑁 + 1 ) ) ∈ ℝ+ ) |
| 76 | 74 75 | syl | ⊢ ( 𝑁 ∈ ℕ → ( 𝐴 ‘ ( 𝑁 + 1 ) ) ∈ ℝ+ ) |
| 77 | 76 | relogcld | ⊢ ( 𝑁 ∈ ℕ → ( log ‘ ( 𝐴 ‘ ( 𝑁 + 1 ) ) ) ∈ ℝ ) |
| 78 | nfcv | ⊢ Ⅎ 𝑛 ( 𝑁 + 1 ) | |
| 79 | 67 78 | nffv | ⊢ Ⅎ 𝑛 ( 𝐴 ‘ ( 𝑁 + 1 ) ) |
| 80 | 65 79 | nffv | ⊢ Ⅎ 𝑛 ( log ‘ ( 𝐴 ‘ ( 𝑁 + 1 ) ) ) |
| 81 | 2fveq3 | ⊢ ( 𝑛 = ( 𝑁 + 1 ) → ( log ‘ ( 𝐴 ‘ 𝑛 ) ) = ( log ‘ ( 𝐴 ‘ ( 𝑁 + 1 ) ) ) ) | |
| 82 | 78 80 81 2 | fvmptf | ⊢ ( ( ( 𝑁 + 1 ) ∈ ℕ ∧ ( log ‘ ( 𝐴 ‘ ( 𝑁 + 1 ) ) ) ∈ ℝ ) → ( 𝐵 ‘ ( 𝑁 + 1 ) ) = ( log ‘ ( 𝐴 ‘ ( 𝑁 + 1 ) ) ) ) |
| 83 | 74 77 82 | syl2anc | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ ( 𝑁 + 1 ) ) = ( log ‘ ( 𝐴 ‘ ( 𝑁 + 1 ) ) ) ) |
| 84 | 83 77 | eqeltrd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ ( 𝑁 + 1 ) ) ∈ ℝ ) |
| 85 | 73 84 | resubcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ∈ ℝ ) |
| 86 | 31 29 | remulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 1 ) ∈ ℝ ) |
| 87 | 0le2 | ⊢ 0 ≤ 2 | |
| 88 | 87 | a1i | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ 2 ) |
| 89 | 0le1 | ⊢ 0 ≤ 1 | |
| 90 | 89 | a1i | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ 1 ) |
| 91 | 31 29 88 90 | mulge0d | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ ( 2 · 1 ) ) |
| 92 | 86 91 | ge0p1rpd | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 1 ) + 1 ) ∈ ℝ+ ) |
| 93 | 92 | rpreccld | ⊢ ( 𝑁 ∈ ℕ → ( 1 / ( ( 2 · 1 ) + 1 ) ) ∈ ℝ+ ) |
| 94 | 39 | rpge0d | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ 𝑁 ) |
| 95 | 31 32 88 94 | mulge0d | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ ( 2 · 𝑁 ) ) |
| 96 | 33 95 | ge0p1rpd | ⊢ ( 𝑁 ∈ ℕ → ( ( 2 · 𝑁 ) + 1 ) ∈ ℝ+ ) |
| 97 | 96 | rpreccld | ⊢ ( 𝑁 ∈ ℕ → ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ∈ ℝ+ ) |
| 98 | 2z | ⊢ 2 ∈ ℤ | |
| 99 | 98 | a1i | ⊢ ( 𝑁 ∈ ℕ → 2 ∈ ℤ ) |
| 100 | 1z | ⊢ 1 ∈ ℤ | |
| 101 | 100 | a1i | ⊢ ( 𝑁 ∈ ℕ → 1 ∈ ℤ ) |
| 102 | 99 101 | zmulcld | ⊢ ( 𝑁 ∈ ℕ → ( 2 · 1 ) ∈ ℤ ) |
| 103 | 97 102 | rpexpcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ∈ ℝ+ ) |
| 104 | 93 103 | rpmulcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 1 / ( ( 2 · 1 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 1 ) ) ) ∈ ℝ+ ) |
| 105 | 52 104 | eqeltrd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐾 ‘ 1 ) ∈ ℝ+ ) |
| 106 | 105 | rpgt0d | ⊢ ( 𝑁 ∈ ℕ → 0 < ( 𝐾 ‘ 1 ) ) |
| 107 | 85 61 | resubcld | ⊢ ( 𝑁 ∈ ℕ → ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( 𝐾 ‘ 1 ) ) ∈ ℝ ) |
| 108 | eqid | ⊢ ( ℤ≥ ‘ ( 1 + 1 ) ) = ( ℤ≥ ‘ ( 1 + 1 ) ) | |
| 109 | 101 | peano2zd | ⊢ ( 𝑁 ∈ ℕ → ( 1 + 1 ) ∈ ℤ ) |
| 110 | nnuz | ⊢ ℕ = ( ℤ≥ ‘ 1 ) | |
| 111 | 3 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝐾 = ( 𝑘 ∈ ℕ ↦ ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) ) ) |
| 112 | oveq2 | ⊢ ( 𝑘 = 𝑗 → ( 2 · 𝑘 ) = ( 2 · 𝑗 ) ) | |
| 113 | 112 | oveq1d | ⊢ ( 𝑘 = 𝑗 → ( ( 2 · 𝑘 ) + 1 ) = ( ( 2 · 𝑗 ) + 1 ) ) |
| 114 | 113 | oveq2d | ⊢ ( 𝑘 = 𝑗 → ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) = ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) ) |
| 115 | 112 | oveq2d | ⊢ ( 𝑘 = 𝑗 → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) = ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) |
| 116 | 114 115 | oveq12d | ⊢ ( 𝑘 = 𝑗 → ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) = ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ) |
| 117 | 116 | adantl | ⊢ ( ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) ∧ 𝑘 = 𝑗 ) → ( ( 1 / ( ( 2 · 𝑘 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑘 ) ) ) = ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ) |
| 118 | simpr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝑗 ∈ ℕ ) | |
| 119 | 2cnd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 2 ∈ ℂ ) | |
| 120 | nncn | ⊢ ( 𝑗 ∈ ℕ → 𝑗 ∈ ℂ ) | |
| 121 | 120 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝑗 ∈ ℂ ) |
| 122 | 119 121 | mulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 2 · 𝑗 ) ∈ ℂ ) |
| 123 | 1cnd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 1 ∈ ℂ ) | |
| 124 | 122 123 | addcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 2 · 𝑗 ) + 1 ) ∈ ℂ ) |
| 125 | 0red | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 0 ∈ ℝ ) | |
| 126 | 1red | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 1 ∈ ℝ ) | |
| 127 | 30 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 2 ∈ ℝ ) |
| 128 | nnre | ⊢ ( 𝑗 ∈ ℕ → 𝑗 ∈ ℝ ) | |
| 129 | 128 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝑗 ∈ ℝ ) |
| 130 | 127 129 | remulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 2 · 𝑗 ) ∈ ℝ ) |
| 131 | 130 126 | readdcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 2 · 𝑗 ) + 1 ) ∈ ℝ ) |
| 132 | 35 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 0 < 1 ) |
| 133 | 37 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 2 ∈ ℝ+ ) |
| 134 | nnrp | ⊢ ( 𝑗 ∈ ℕ → 𝑗 ∈ ℝ+ ) | |
| 135 | 134 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝑗 ∈ ℝ+ ) |
| 136 | 133 135 | rpmulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 2 · 𝑗 ) ∈ ℝ+ ) |
| 137 | 126 136 | ltaddrp2d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 1 < ( ( 2 · 𝑗 ) + 1 ) ) |
| 138 | 125 126 131 132 137 | lttrd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 0 < ( ( 2 · 𝑗 ) + 1 ) ) |
| 139 | 138 | gt0ne0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 2 · 𝑗 ) + 1 ) ≠ 0 ) |
| 140 | 124 139 | reccld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) ∈ ℂ ) |
| 141 | 26 | adantr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝑁 ∈ ℂ ) |
| 142 | 119 141 | mulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 2 · 𝑁 ) ∈ ℂ ) |
| 143 | 142 123 | addcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 2 · 𝑁 ) + 1 ) ∈ ℂ ) |
| 144 | 43 | adantr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 2 · 𝑁 ) + 1 ) ≠ 0 ) |
| 145 | 143 144 | reccld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ∈ ℂ ) |
| 146 | 45 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 2 ∈ ℕ0 ) |
| 147 | nnnn0 | ⊢ ( 𝑗 ∈ ℕ → 𝑗 ∈ ℕ0 ) | |
| 148 | 147 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → 𝑗 ∈ ℕ0 ) |
| 149 | 146 148 | nn0mulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 2 · 𝑗 ) ∈ ℕ0 ) |
| 150 | 145 149 | expcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ∈ ℂ ) |
| 151 | 140 150 | mulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ∈ ℂ ) |
| 152 | 111 117 118 151 | fvmptd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 𝐾 ‘ 𝑗 ) = ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ) |
| 153 | 0red | ⊢ ( 𝑗 ∈ ℕ → 0 ∈ ℝ ) | |
| 154 | 1red | ⊢ ( 𝑗 ∈ ℕ → 1 ∈ ℝ ) | |
| 155 | 30 | a1i | ⊢ ( 𝑗 ∈ ℕ → 2 ∈ ℝ ) |
| 156 | 155 128 | remulcld | ⊢ ( 𝑗 ∈ ℕ → ( 2 · 𝑗 ) ∈ ℝ ) |
| 157 | 156 154 | readdcld | ⊢ ( 𝑗 ∈ ℕ → ( ( 2 · 𝑗 ) + 1 ) ∈ ℝ ) |
| 158 | 35 | a1i | ⊢ ( 𝑗 ∈ ℕ → 0 < 1 ) |
| 159 | 37 | a1i | ⊢ ( 𝑗 ∈ ℕ → 2 ∈ ℝ+ ) |
| 160 | 159 134 | rpmulcld | ⊢ ( 𝑗 ∈ ℕ → ( 2 · 𝑗 ) ∈ ℝ+ ) |
| 161 | 154 160 | ltaddrp2d | ⊢ ( 𝑗 ∈ ℕ → 1 < ( ( 2 · 𝑗 ) + 1 ) ) |
| 162 | 153 154 157 158 161 | lttrd | ⊢ ( 𝑗 ∈ ℕ → 0 < ( ( 2 · 𝑗 ) + 1 ) ) |
| 163 | 162 | gt0ne0d | ⊢ ( 𝑗 ∈ ℕ → ( ( 2 · 𝑗 ) + 1 ) ≠ 0 ) |
| 164 | 163 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 2 · 𝑗 ) + 1 ) ≠ 0 ) |
| 165 | 124 164 | reccld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) ∈ ℂ ) |
| 166 | 165 150 | mulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ∈ ℂ ) |
| 167 | 152 166 | eqeltrd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) → ( 𝐾 ‘ 𝑗 ) ∈ ℂ ) |
| 168 | eqid | ⊢ ( 𝑛 ∈ ℕ ↦ ( ( ( ( 1 + ( 2 · 𝑛 ) ) / 2 ) · ( log ‘ ( ( 𝑛 + 1 ) / 𝑛 ) ) ) − 1 ) ) = ( 𝑛 ∈ ℕ ↦ ( ( ( ( 1 + ( 2 · 𝑛 ) ) / 2 ) · ( log ‘ ( ( 𝑛 + 1 ) / 𝑛 ) ) ) − 1 ) ) | |
| 169 | 1 2 168 3 | stirlinglem9 | ⊢ ( 𝑁 ∈ ℕ → seq 1 ( + , 𝐾 ) ⇝ ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ) |
| 170 | 110 13 167 169 | clim2ser | ⊢ ( 𝑁 ∈ ℕ → seq ( 1 + 1 ) ( + , 𝐾 ) ⇝ ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( seq 1 ( + , 𝐾 ) ‘ 1 ) ) ) |
| 171 | peano2nn | ⊢ ( 1 ∈ ℕ → ( 1 + 1 ) ∈ ℕ ) | |
| 172 | uznnssnn | ⊢ ( ( 1 + 1 ) ∈ ℕ → ( ℤ≥ ‘ ( 1 + 1 ) ) ⊆ ℕ ) | |
| 173 | 12 171 172 | mp2b | ⊢ ( ℤ≥ ‘ ( 1 + 1 ) ) ⊆ ℕ |
| 174 | 173 | a1i | ⊢ ( 𝑁 ∈ ℕ → ( ℤ≥ ‘ ( 1 + 1 ) ) ⊆ ℕ ) |
| 175 | 174 | sseld | ⊢ ( 𝑁 ∈ ℕ → ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 𝑗 ∈ ℕ ) ) |
| 176 | 175 | imdistani | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ℕ ) ) |
| 177 | 176 152 | syl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 𝐾 ‘ 𝑗 ) = ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ) |
| 178 | 30 | a1i | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 2 ∈ ℝ ) |
| 179 | eluzelre | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 𝑗 ∈ ℝ ) | |
| 180 | 178 179 | remulcld | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → ( 2 · 𝑗 ) ∈ ℝ ) |
| 181 | 1red | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 1 ∈ ℝ ) | |
| 182 | 180 181 | readdcld | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → ( ( 2 · 𝑗 ) + 1 ) ∈ ℝ ) |
| 183 | 173 | sseli | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 𝑗 ∈ ℕ ) |
| 184 | 183 163 | syl | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → ( ( 2 · 𝑗 ) + 1 ) ≠ 0 ) |
| 185 | 182 184 | rereccld | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) ∈ ℝ ) |
| 186 | 185 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) ∈ ℝ ) |
| 187 | 34 | adantr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( ( 2 · 𝑁 ) + 1 ) ∈ ℝ ) |
| 188 | 43 | adantr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( ( 2 · 𝑁 ) + 1 ) ≠ 0 ) |
| 189 | 187 188 | rereccld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ∈ ℝ ) |
| 190 | 176 149 | syl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 2 · 𝑗 ) ∈ ℕ0 ) |
| 191 | 189 190 | reexpcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ∈ ℝ ) |
| 192 | 186 191 | remulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ∈ ℝ ) |
| 193 | 177 192 | eqeltrd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 𝐾 ‘ 𝑗 ) ∈ ℝ ) |
| 194 | 1red | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 1 ∈ ℝ ) | |
| 195 | 30 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 2 ∈ ℝ ) |
| 196 | 176 129 | syl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 𝑗 ∈ ℝ ) |
| 197 | 195 196 | remulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 2 · 𝑗 ) ∈ ℝ ) |
| 198 | 87 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ 2 ) |
| 199 | 0red | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 0 ∈ ℝ ) | |
| 200 | 87 | a1i | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 0 ≤ 2 ) |
| 201 | 1p1e2 | ⊢ ( 1 + 1 ) = 2 | |
| 202 | eluzle | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → ( 1 + 1 ) ≤ 𝑗 ) | |
| 203 | 201 202 | eqbrtrrid | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 2 ≤ 𝑗 ) |
| 204 | 199 178 179 200 203 | letrd | ⊢ ( 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) → 0 ≤ 𝑗 ) |
| 205 | 204 | adantl | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ 𝑗 ) |
| 206 | 195 196 198 205 | mulge0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( 2 · 𝑗 ) ) |
| 207 | 197 206 | ge0p1rpd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( ( 2 · 𝑗 ) + 1 ) ∈ ℝ+ ) |
| 208 | 89 | a1i | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ 1 ) |
| 209 | 194 207 208 | divge0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) ) |
| 210 | 32 | adantr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 𝑁 ∈ ℝ ) |
| 211 | 195 210 | remulcld | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( 2 · 𝑁 ) ∈ ℝ ) |
| 212 | 94 | adantr | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ 𝑁 ) |
| 213 | 195 210 198 212 | mulge0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( 2 · 𝑁 ) ) |
| 214 | 211 213 | ge0p1rpd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → ( ( 2 · 𝑁 ) + 1 ) ∈ ℝ+ ) |
| 215 | 194 214 208 | divge0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ) |
| 216 | 189 190 215 | expge0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) |
| 217 | 186 191 209 216 | mulge0d | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( ( 1 / ( ( 2 · 𝑗 ) + 1 ) ) · ( ( 1 / ( ( 2 · 𝑁 ) + 1 ) ) ↑ ( 2 · 𝑗 ) ) ) ) |
| 218 | 217 177 | breqtrrd | ⊢ ( ( 𝑁 ∈ ℕ ∧ 𝑗 ∈ ( ℤ≥ ‘ ( 1 + 1 ) ) ) → 0 ≤ ( 𝐾 ‘ 𝑗 ) ) |
| 219 | 108 109 170 193 218 | iserge0 | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( seq 1 ( + , 𝐾 ) ‘ 1 ) ) ) |
| 220 | seq1 | ⊢ ( 1 ∈ ℤ → ( seq 1 ( + , 𝐾 ) ‘ 1 ) = ( 𝐾 ‘ 1 ) ) | |
| 221 | 100 220 | mp1i | ⊢ ( 𝑁 ∈ ℕ → ( seq 1 ( + , 𝐾 ) ‘ 1 ) = ( 𝐾 ‘ 1 ) ) |
| 222 | 221 | oveq2d | ⊢ ( 𝑁 ∈ ℕ → ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( seq 1 ( + , 𝐾 ) ‘ 1 ) ) = ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( 𝐾 ‘ 1 ) ) ) |
| 223 | 219 222 | breqtrd | ⊢ ( 𝑁 ∈ ℕ → 0 ≤ ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( 𝐾 ‘ 1 ) ) ) |
| 224 | 4 107 61 223 | leadd1dd | ⊢ ( 𝑁 ∈ ℕ → ( 0 + ( 𝐾 ‘ 1 ) ) ≤ ( ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( 𝐾 ‘ 1 ) ) + ( 𝐾 ‘ 1 ) ) ) |
| 225 | 52 51 | eqeltrd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐾 ‘ 1 ) ∈ ℂ ) |
| 226 | 225 | addlidd | ⊢ ( 𝑁 ∈ ℕ → ( 0 + ( 𝐾 ‘ 1 ) ) = ( 𝐾 ‘ 1 ) ) |
| 227 | 73 | recnd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ 𝑁 ) ∈ ℂ ) |
| 228 | 84 | recnd | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ ( 𝑁 + 1 ) ) ∈ ℂ ) |
| 229 | 227 228 | subcld | ⊢ ( 𝑁 ∈ ℕ → ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ∈ ℂ ) |
| 230 | 229 225 | npcand | ⊢ ( 𝑁 ∈ ℕ → ( ( ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) − ( 𝐾 ‘ 1 ) ) + ( 𝐾 ‘ 1 ) ) = ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ) |
| 231 | 224 226 230 | 3brtr3d | ⊢ ( 𝑁 ∈ ℕ → ( 𝐾 ‘ 1 ) ≤ ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ) |
| 232 | 4 61 85 106 231 | ltletrd | ⊢ ( 𝑁 ∈ ℕ → 0 < ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ) |
| 233 | 84 73 | posdifd | ⊢ ( 𝑁 ∈ ℕ → ( ( 𝐵 ‘ ( 𝑁 + 1 ) ) < ( 𝐵 ‘ 𝑁 ) ↔ 0 < ( ( 𝐵 ‘ 𝑁 ) − ( 𝐵 ‘ ( 𝑁 + 1 ) ) ) ) ) |
| 234 | 232 233 | mpbird | ⊢ ( 𝑁 ∈ ℕ → ( 𝐵 ‘ ( 𝑁 + 1 ) ) < ( 𝐵 ‘ 𝑁 ) ) |