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Mirrors > Home > MPE Home > Th. List > bcn0 | Structured version Visualization version GIF version |
Description: 𝑁 choose 0 is 1. Remark in [Gleason] p. 296. (Contributed by NM, 17-Jun-2005.) (Revised by Mario Carneiro, 8-Nov-2013.) |
Ref | Expression |
---|---|
bcn0 | ⊢ (𝑁 ∈ ℕ0 → (𝑁C0) = 1) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 0elfz 13644 | . . 3 ⊢ (𝑁 ∈ ℕ0 → 0 ∈ (0...𝑁)) | |
2 | bcval2 14315 | . . 3 ⊢ (0 ∈ (0...𝑁) → (𝑁C0) = ((!‘𝑁) / ((!‘(𝑁 − 0)) · (!‘0)))) | |
3 | 1, 2 | syl 17 | . 2 ⊢ (𝑁 ∈ ℕ0 → (𝑁C0) = ((!‘𝑁) / ((!‘(𝑁 − 0)) · (!‘0)))) |
4 | nn0cn 12526 | . . . . . . . 8 ⊢ (𝑁 ∈ ℕ0 → 𝑁 ∈ ℂ) | |
5 | 4 | subid1d 11599 | . . . . . . 7 ⊢ (𝑁 ∈ ℕ0 → (𝑁 − 0) = 𝑁) |
6 | 5 | fveq2d 6895 | . . . . . 6 ⊢ (𝑁 ∈ ℕ0 → (!‘(𝑁 − 0)) = (!‘𝑁)) |
7 | fac0 14286 | . . . . . 6 ⊢ (!‘0) = 1 | |
8 | oveq12 7423 | . . . . . 6 ⊢ (((!‘(𝑁 − 0)) = (!‘𝑁) ∧ (!‘0) = 1) → ((!‘(𝑁 − 0)) · (!‘0)) = ((!‘𝑁) · 1)) | |
9 | 6, 7, 8 | sylancl 584 | . . . . 5 ⊢ (𝑁 ∈ ℕ0 → ((!‘(𝑁 − 0)) · (!‘0)) = ((!‘𝑁) · 1)) |
10 | faccl 14293 | . . . . . . 7 ⊢ (𝑁 ∈ ℕ0 → (!‘𝑁) ∈ ℕ) | |
11 | 10 | nncnd 12272 | . . . . . 6 ⊢ (𝑁 ∈ ℕ0 → (!‘𝑁) ∈ ℂ) |
12 | 11 | mulridd 11270 | . . . . 5 ⊢ (𝑁 ∈ ℕ0 → ((!‘𝑁) · 1) = (!‘𝑁)) |
13 | 9, 12 | eqtrd 2766 | . . . 4 ⊢ (𝑁 ∈ ℕ0 → ((!‘(𝑁 − 0)) · (!‘0)) = (!‘𝑁)) |
14 | 13 | oveq2d 7430 | . . 3 ⊢ (𝑁 ∈ ℕ0 → ((!‘𝑁) / ((!‘(𝑁 − 0)) · (!‘0))) = ((!‘𝑁) / (!‘𝑁))) |
15 | facne0 14296 | . . . 4 ⊢ (𝑁 ∈ ℕ0 → (!‘𝑁) ≠ 0) | |
16 | 11, 15 | dividd 12031 | . . 3 ⊢ (𝑁 ∈ ℕ0 → ((!‘𝑁) / (!‘𝑁)) = 1) |
17 | 14, 16 | eqtrd 2766 | . 2 ⊢ (𝑁 ∈ ℕ0 → ((!‘𝑁) / ((!‘(𝑁 − 0)) · (!‘0))) = 1) |
18 | 3, 17 | eqtrd 2766 | 1 ⊢ (𝑁 ∈ ℕ0 → (𝑁C0) = 1) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 = wceq 1534 ∈ wcel 2099 ‘cfv 6544 (class class class)co 7414 0cc0 11147 1c1 11148 · cmul 11152 − cmin 11483 / cdiv 11910 ℕ0cn0 12516 ...cfz 13530 !cfa 14283 Ccbc 14312 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1790 ax-4 1804 ax-5 1906 ax-6 1964 ax-7 2004 ax-8 2101 ax-9 2109 ax-10 2130 ax-11 2147 ax-12 2167 ax-ext 2697 ax-sep 5295 ax-nul 5302 ax-pow 5360 ax-pr 5424 ax-un 7736 ax-cnex 11203 ax-resscn 11204 ax-1cn 11205 ax-icn 11206 ax-addcl 11207 ax-addrcl 11208 ax-mulcl 11209 ax-mulrcl 11210 ax-mulcom 11211 ax-addass 11212 ax-mulass 11213 ax-distr 11214 ax-i2m1 11215 ax-1ne0 11216 ax-1rid 11217 ax-rnegex 11218 ax-rrecex 11219 ax-cnre 11220 ax-pre-lttri 11221 ax-pre-lttrn 11222 ax-pre-ltadd 11223 ax-pre-mulgt0 11224 |
This theorem depends on definitions: df-bi 206 df-an 395 df-or 846 df-3or 1085 df-3an 1086 df-tru 1537 df-fal 1547 df-ex 1775 df-nf 1779 df-sb 2061 df-mo 2529 df-eu 2558 df-clab 2704 df-cleq 2718 df-clel 2803 df-nfc 2878 df-ne 2931 df-nel 3037 df-ral 3052 df-rex 3061 df-rmo 3365 df-reu 3366 df-rab 3421 df-v 3465 df-sbc 3777 df-csb 3893 df-dif 3950 df-un 3952 df-in 3954 df-ss 3964 df-pss 3967 df-nul 4324 df-if 4525 df-pw 4600 df-sn 4625 df-pr 4627 df-op 4631 df-uni 4907 df-iun 4996 df-br 5145 df-opab 5207 df-mpt 5228 df-tr 5262 df-id 5571 df-eprel 5577 df-po 5585 df-so 5586 df-fr 5628 df-we 5630 df-xp 5679 df-rel 5680 df-cnv 5681 df-co 5682 df-dm 5683 df-rn 5684 df-res 5685 df-ima 5686 df-pred 6303 df-ord 6369 df-on 6370 df-lim 6371 df-suc 6372 df-iota 6496 df-fun 6546 df-fn 6547 df-f 6548 df-f1 6549 df-fo 6550 df-f1o 6551 df-fv 6552 df-riota 7370 df-ov 7417 df-oprab 7418 df-mpo 7419 df-om 7867 df-1st 7993 df-2nd 7994 df-frecs 8286 df-wrecs 8317 df-recs 8391 df-rdg 8430 df-er 8724 df-en 8965 df-dom 8966 df-sdom 8967 df-pnf 11289 df-mnf 11290 df-xr 11291 df-ltxr 11292 df-le 11293 df-sub 11485 df-neg 11486 df-div 11911 df-nn 12257 df-n0 12517 df-z 12603 df-uz 12867 df-fz 13531 df-seq 14014 df-fac 14284 df-bc 14313 |
This theorem is referenced by: bcnn 14322 bcpasc 14331 bccl 14332 hashbc 14463 hashf1 14469 binom 15827 bcxmas 15832 bpoly1 16046 bpoly2 16052 bpoly3 16053 bpoly4 16054 sylow1lem1 19590 srgbinom 20208 freshmansdream 21566 bclbnd 27304 dvnmul 45598 |
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