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Mathbox for Thierry Arnoux |
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Mirrors > Home > MPE Home > Th. List > Mathboxes > signsvf1 | Structured version Visualization version GIF version |
Description: In a single-letter word, which represents a constant polynomial, there is no change of sign. (Contributed by Thierry Arnoux, 8-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 |
---|---|
signsvf1 | ⊢ (𝐾 ∈ ℝ → (𝑉‘〈“𝐾”〉) = 0) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | s1cl 14637 | . . 3 ⊢ (𝐾 ∈ ℝ → 〈“𝐾”〉 ∈ Word 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 | signsvvfval 34572 | . . 3 ⊢ (〈“𝐾”〉 ∈ Word ℝ → (𝑉‘〈“𝐾”〉) = Σ𝑗 ∈ (1..^(♯‘〈“𝐾”〉))if(((𝑇‘〈“𝐾”〉)‘𝑗) ≠ ((𝑇‘〈“𝐾”〉)‘(𝑗 − 1)), 1, 0)) |
7 | 1, 6 | syl 17 | . 2 ⊢ (𝐾 ∈ ℝ → (𝑉‘〈“𝐾”〉) = Σ𝑗 ∈ (1..^(♯‘〈“𝐾”〉))if(((𝑇‘〈“𝐾”〉)‘𝑗) ≠ ((𝑇‘〈“𝐾”〉)‘(𝑗 − 1)), 1, 0)) |
8 | s1len 14641 | . . . . . 6 ⊢ (♯‘〈“𝐾”〉) = 1 | |
9 | 8 | oveq2i 7442 | . . . . 5 ⊢ (1..^(♯‘〈“𝐾”〉)) = (1..^1) |
10 | fzo0 13720 | . . . . 5 ⊢ (1..^1) = ∅ | |
11 | 9, 10 | eqtri 2763 | . . . 4 ⊢ (1..^(♯‘〈“𝐾”〉)) = ∅ |
12 | 11 | sumeq1i 15730 | . . 3 ⊢ Σ𝑗 ∈ (1..^(♯‘〈“𝐾”〉))if(((𝑇‘〈“𝐾”〉)‘𝑗) ≠ ((𝑇‘〈“𝐾”〉)‘(𝑗 − 1)), 1, 0) = Σ𝑗 ∈ ∅ if(((𝑇‘〈“𝐾”〉)‘𝑗) ≠ ((𝑇‘〈“𝐾”〉)‘(𝑗 − 1)), 1, 0) |
13 | sum0 15754 | . . 3 ⊢ Σ𝑗 ∈ ∅ if(((𝑇‘〈“𝐾”〉)‘𝑗) ≠ ((𝑇‘〈“𝐾”〉)‘(𝑗 − 1)), 1, 0) = 0 | |
14 | 12, 13 | eqtri 2763 | . 2 ⊢ Σ𝑗 ∈ (1..^(♯‘〈“𝐾”〉))if(((𝑇‘〈“𝐾”〉)‘𝑗) ≠ ((𝑇‘〈“𝐾”〉)‘(𝑗 − 1)), 1, 0) = 0 |
15 | 7, 14 | eqtrdi 2791 | 1 ⊢ (𝐾 ∈ ℝ → (𝑉‘〈“𝐾”〉) = 0) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 = wceq 1537 ∈ wcel 2106 ≠ wne 2938 ∅c0 4339 ifcif 4531 {cpr 4633 {ctp 4635 〈cop 4637 ↦ cmpt 5231 ‘cfv 6563 (class class class)co 7431 ∈ cmpo 7433 ℝcr 11152 0cc0 11153 1c1 11154 − cmin 11490 -cneg 11491 ...cfz 13544 ..^cfzo 13691 ♯chash 14366 Word cword 14549 〈“cs1 14630 sgncsgn 15122 Σcsu 15719 ndxcnx 17227 Basecbs 17245 +gcplusg 17298 Σg cgsu 17487 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1792 ax-4 1806 ax-5 1908 ax-6 1965 ax-7 2005 ax-8 2108 ax-9 2116 ax-10 2139 ax-11 2155 ax-12 2175 ax-ext 2706 ax-rep 5285 ax-sep 5302 ax-nul 5312 ax-pow 5371 ax-pr 5438 ax-un 7754 ax-inf2 9679 ax-cnex 11209 ax-resscn 11210 ax-1cn 11211 ax-icn 11212 ax-addcl 11213 ax-addrcl 11214 ax-mulcl 11215 ax-mulrcl 11216 ax-mulcom 11217 ax-addass 11218 ax-mulass 11219 ax-distr 11220 ax-i2m1 11221 ax-1ne0 11222 ax-1rid 11223 ax-rnegex 11224 ax-rrecex 11225 ax-cnre 11226 ax-pre-lttri 11227 ax-pre-lttrn 11228 ax-pre-ltadd 11229 ax-pre-mulgt0 11230 ax-pre-sup 11231 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3or 1087 df-3an 1088 df-tru 1540 df-fal 1550 df-ex 1777 df-nf 1781 df-sb 2063 df-mo 2538 df-eu 2567 df-clab 2713 df-cleq 2727 df-clel 2814 df-nfc 2890 df-ne 2939 df-nel 3045 df-ral 3060 df-rex 3069 df-rmo 3378 df-reu 3379 df-rab 3434 df-v 3480 df-sbc 3792 df-csb 3909 df-dif 3966 df-un 3968 df-in 3970 df-ss 3980 df-pss 3983 df-nul 4340 df-if 4532 df-pw 4607 df-sn 4632 df-pr 4634 df-op 4638 df-uni 4913 df-int 4952 df-iun 4998 df-br 5149 df-opab 5211 df-mpt 5232 df-tr 5266 df-id 5583 df-eprel 5589 df-po 5597 df-so 5598 df-fr 5641 df-se 5642 df-we 5643 df-xp 5695 df-rel 5696 df-cnv 5697 df-co 5698 df-dm 5699 df-rn 5700 df-res 5701 df-ima 5702 df-pred 6323 df-ord 6389 df-on 6390 df-lim 6391 df-suc 6392 df-iota 6516 df-fun 6565 df-fn 6566 df-f 6567 df-f1 6568 df-fo 6569 df-f1o 6570 df-fv 6571 df-isom 6572 df-riota 7388 df-ov 7434 df-oprab 7435 df-mpo 7436 df-om 7888 df-1st 8013 df-2nd 8014 df-frecs 8305 df-wrecs 8336 df-recs 8410 df-rdg 8449 df-1o 8505 df-er 8744 df-en 8985 df-dom 8986 df-sdom 8987 df-fin 8988 df-sup 9480 df-oi 9548 df-card 9977 df-pnf 11295 df-mnf 11296 df-xr 11297 df-ltxr 11298 df-le 11299 df-sub 11492 df-neg 11493 df-div 11919 df-nn 12265 df-2 12327 df-3 12328 df-n0 12525 df-z 12612 df-uz 12877 df-rp 13033 df-fz 13545 df-fzo 13692 df-seq 14040 df-exp 14100 df-hash 14367 df-word 14550 df-s1 14631 df-cj 15135 df-re 15136 df-im 15137 df-sqrt 15271 df-abs 15272 df-clim 15521 df-sum 15720 |
This theorem is referenced by: (None) |
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