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Mathbox for Thierry Arnoux |
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Mirrors > Home > MPE Home > Th. List > Mathboxes > signlem0 | Structured version Visualization version GIF version |
Description: Adding a zero as the highest coefficient does not change the parity of the sign changes. (Contributed by Thierry Arnoux, 12-Oct-2018.) |
Ref | Expression |
---|---|
signsv.p | ⊢ ⨣ = (𝑎 ∈ {-1, 0, 1}, 𝑏 ∈ {-1, 0, 1} ↦ if(𝑏 = 0, 𝑎, 𝑏)) |
signsv.w | ⊢ 𝑊 = {〈(Base‘ndx), {-1, 0, 1}〉, 〈(+g‘ndx), ⨣ 〉} |
signsv.t | ⊢ 𝑇 = (𝑓 ∈ Word ℝ ↦ (𝑛 ∈ (0..^(♯‘𝑓)) ↦ (𝑊 Σg (𝑖 ∈ (0...𝑛) ↦ (sgn‘(𝑓‘𝑖)))))) |
signsv.v | ⊢ 𝑉 = (𝑓 ∈ Word ℝ ↦ Σ𝑗 ∈ (1..^(♯‘𝑓))if(((𝑇‘𝑓)‘𝑗) ≠ ((𝑇‘𝑓)‘(𝑗 − 1)), 1, 0)) |
Ref | Expression |
---|---|
signlem0 | ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (𝑉‘(𝐹 ++ 〈“0”〉)) = (𝑉‘𝐹)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 0re 10439 | . . 3 ⊢ 0 ∈ ℝ | |
2 | signsv.p | . . . 4 ⊢ ⨣ = (𝑎 ∈ {-1, 0, 1}, 𝑏 ∈ {-1, 0, 1} ↦ if(𝑏 = 0, 𝑎, 𝑏)) | |
3 | signsv.w | . . . 4 ⊢ 𝑊 = {〈(Base‘ndx), {-1, 0, 1}〉, 〈(+g‘ndx), ⨣ 〉} | |
4 | signsv.t | . . . 4 ⊢ 𝑇 = (𝑓 ∈ Word ℝ ↦ (𝑛 ∈ (0..^(♯‘𝑓)) ↦ (𝑊 Σg (𝑖 ∈ (0...𝑛) ↦ (sgn‘(𝑓‘𝑖)))))) | |
5 | signsv.v | . . . 4 ⊢ 𝑉 = (𝑓 ∈ Word ℝ ↦ Σ𝑗 ∈ (1..^(♯‘𝑓))if(((𝑇‘𝑓)‘𝑗) ≠ ((𝑇‘𝑓)‘(𝑗 − 1)), 1, 0)) | |
6 | 2, 3, 4, 5 | signsvfn 31532 | . . 3 ⊢ (((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) ∧ 0 ∈ ℝ) → (𝑉‘(𝐹 ++ 〈“0”〉)) = ((𝑉‘𝐹) + if((((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) < 0, 1, 0))) |
7 | 1, 6 | mpan2 679 | . 2 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (𝑉‘(𝐹 ++ 〈“0”〉)) = ((𝑉‘𝐹) + if((((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) < 0, 1, 0))) |
8 | 1 | ltnri 10547 | . . . . 5 ⊢ ¬ 0 < 0 |
9 | neg1cn 11559 | . . . . . . . . 9 ⊢ -1 ∈ ℂ | |
10 | ax-1cn 10391 | . . . . . . . . 9 ⊢ 1 ∈ ℂ | |
11 | prssi 4624 | . . . . . . . . 9 ⊢ ((-1 ∈ ℂ ∧ 1 ∈ ℂ) → {-1, 1} ⊆ ℂ) | |
12 | 9, 10, 11 | mp2an 680 | . . . . . . . 8 ⊢ {-1, 1} ⊆ ℂ |
13 | simpl 475 | . . . . . . . . . . 11 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → 𝐹 ∈ (Word ℝ ∖ {∅})) | |
14 | eldifsn 4589 | . . . . . . . . . . 11 ⊢ (𝐹 ∈ (Word ℝ ∖ {∅}) ↔ (𝐹 ∈ Word ℝ ∧ 𝐹 ≠ ∅)) | |
15 | 13, 14 | sylib 210 | . . . . . . . . . 10 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (𝐹 ∈ Word ℝ ∧ 𝐹 ≠ ∅)) |
16 | lennncl 13693 | . . . . . . . . . 10 ⊢ ((𝐹 ∈ Word ℝ ∧ 𝐹 ≠ ∅) → (♯‘𝐹) ∈ ℕ) | |
17 | fzo0end 12942 | . . . . . . . . . 10 ⊢ ((♯‘𝐹) ∈ ℕ → ((♯‘𝐹) − 1) ∈ (0..^(♯‘𝐹))) | |
18 | 15, 16, 17 | 3syl 18 | . . . . . . . . 9 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ((♯‘𝐹) − 1) ∈ (0..^(♯‘𝐹))) |
19 | 2, 3, 4, 5 | signstfvcl 31522 | . . . . . . . . 9 ⊢ (((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) ∧ ((♯‘𝐹) − 1) ∈ (0..^(♯‘𝐹))) → ((𝑇‘𝐹)‘((♯‘𝐹) − 1)) ∈ {-1, 1}) |
20 | 18, 19 | mpdan 675 | . . . . . . . 8 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ((𝑇‘𝐹)‘((♯‘𝐹) − 1)) ∈ {-1, 1}) |
21 | 12, 20 | sseldi 3849 | . . . . . . 7 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ((𝑇‘𝐹)‘((♯‘𝐹) − 1)) ∈ ℂ) |
22 | 21 | mul01d 10637 | . . . . . 6 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) = 0) |
23 | 22 | breq1d 4935 | . . . . 5 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ((((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) < 0 ↔ 0 < 0)) |
24 | 8, 23 | mtbiri 319 | . . . 4 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ¬ (((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) < 0) |
25 | 24 | iffalsed 4355 | . . 3 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → if((((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) < 0, 1, 0) = 0) |
26 | 25 | oveq2d 6990 | . 2 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ((𝑉‘𝐹) + if((((𝑇‘𝐹)‘((♯‘𝐹) − 1)) · 0) < 0, 1, 0)) = ((𝑉‘𝐹) + 0)) |
27 | 2, 3, 4, 5 | signsvvf 31529 | . . . . . 6 ⊢ 𝑉:Word ℝ⟶ℕ0 |
28 | 27 | a1i 11 | . . . . 5 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → 𝑉:Word ℝ⟶ℕ0) |
29 | 13 | eldifad 3834 | . . . . 5 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → 𝐹 ∈ Word ℝ) |
30 | 28, 29 | ffvelrnd 6675 | . . . 4 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (𝑉‘𝐹) ∈ ℕ0) |
31 | 30 | nn0cnd 11767 | . . 3 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (𝑉‘𝐹) ∈ ℂ) |
32 | 31 | addid1d 10638 | . 2 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → ((𝑉‘𝐹) + 0) = (𝑉‘𝐹)) |
33 | 7, 26, 32 | 3eqtrd 2811 | 1 ⊢ ((𝐹 ∈ (Word ℝ ∖ {∅}) ∧ (𝐹‘0) ≠ 0) → (𝑉‘(𝐹 ++ 〈“0”〉)) = (𝑉‘𝐹)) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∧ wa 387 = wceq 1508 ∈ wcel 2051 ≠ wne 2960 ∖ cdif 3819 ⊆ wss 3822 ∅c0 4172 ifcif 4344 {csn 4435 {cpr 4437 {ctp 4439 〈cop 4441 class class class wbr 4925 ↦ cmpt 5004 ⟶wf 6181 ‘cfv 6185 (class class class)co 6974 ∈ cmpo 6976 ℂcc 10331 ℝcr 10332 0cc0 10333 1c1 10334 + caddc 10336 · cmul 10338 < clt 10472 − cmin 10668 -cneg 10669 ℕcn 11437 ℕ0cn0 11705 ...cfz 12706 ..^cfzo 12847 ♯chash 13503 Word cword 13670 ++ cconcat 13731 〈“cs1 13756 sgncsgn 14304 Σcsu 14901 ndxcnx 16334 Basecbs 16337 +gcplusg 16419 Σg cgsu 16568 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1759 ax-4 1773 ax-5 1870 ax-6 1929 ax-7 1966 ax-8 2053 ax-9 2060 ax-10 2080 ax-11 2094 ax-12 2107 ax-13 2302 ax-ext 2743 ax-rep 5045 ax-sep 5056 ax-nul 5063 ax-pow 5115 ax-pr 5182 ax-un 7277 ax-inf2 8896 ax-cnex 10389 ax-resscn 10390 ax-1cn 10391 ax-icn 10392 ax-addcl 10393 ax-addrcl 10394 ax-mulcl 10395 ax-mulrcl 10396 ax-mulcom 10397 ax-addass 10398 ax-mulass 10399 ax-distr 10400 ax-i2m1 10401 ax-1ne0 10402 ax-1rid 10403 ax-rnegex 10404 ax-rrecex 10405 ax-cnre 10406 ax-pre-lttri 10407 ax-pre-lttrn 10408 ax-pre-ltadd 10409 ax-pre-mulgt0 10410 ax-pre-sup 10411 |
This theorem depends on definitions: df-bi 199 df-an 388 df-or 835 df-3or 1070 df-3an 1071 df-tru 1511 df-fal 1521 df-ex 1744 df-nf 1748 df-sb 2017 df-mo 2548 df-eu 2585 df-clab 2752 df-cleq 2764 df-clel 2839 df-nfc 2911 df-ne 2961 df-nel 3067 df-ral 3086 df-rex 3087 df-reu 3088 df-rmo 3089 df-rab 3090 df-v 3410 df-sbc 3675 df-csb 3780 df-dif 3825 df-un 3827 df-in 3829 df-ss 3836 df-pss 3838 df-nul 4173 df-if 4345 df-pw 4418 df-sn 4436 df-pr 4438 df-tp 4440 df-op 4442 df-uni 4709 df-int 4746 df-iun 4790 df-br 4926 df-opab 4988 df-mpt 5005 df-tr 5027 df-id 5308 df-eprel 5313 df-po 5322 df-so 5323 df-fr 5362 df-se 5363 df-we 5364 df-xp 5409 df-rel 5410 df-cnv 5411 df-co 5412 df-dm 5413 df-rn 5414 df-res 5415 df-ima 5416 df-pred 5983 df-ord 6029 df-on 6030 df-lim 6031 df-suc 6032 df-iota 6149 df-fun 6187 df-fn 6188 df-f 6189 df-f1 6190 df-fo 6191 df-f1o 6192 df-fv 6193 df-isom 6194 df-riota 6935 df-ov 6977 df-oprab 6978 df-mpo 6979 df-om 7395 df-1st 7499 df-2nd 7500 df-supp 7632 df-wrecs 7748 df-recs 7810 df-rdg 7848 df-1o 7903 df-oadd 7907 df-er 8087 df-en 8305 df-dom 8306 df-sdom 8307 df-fin 8308 df-sup 8699 df-oi 8767 df-card 9160 df-pnf 10474 df-mnf 10475 df-xr 10476 df-ltxr 10477 df-le 10478 df-sub 10670 df-neg 10671 df-div 11097 df-nn 11438 df-2 11501 df-3 11502 df-n0 11706 df-xnn0 11778 df-z 11792 df-uz 12057 df-rp 12203 df-fz 12707 df-fzo 12848 df-seq 13183 df-exp 13243 df-hash 13504 df-word 13671 df-lsw 13724 df-concat 13732 df-s1 13757 df-substr 13802 df-pfx 13851 df-sgn 14305 df-cj 14317 df-re 14318 df-im 14319 df-sqrt 14453 df-abs 14454 df-clim 14704 df-sum 14902 df-struct 16339 df-ndx 16340 df-slot 16341 df-base 16343 df-plusg 16432 df-0g 16569 df-gsum 16570 df-mgm 17722 df-sgrp 17764 df-mnd 17775 df-mulg 18024 df-cntz 18230 |
This theorem is referenced by: (None) |
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