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Mirrors > Home > MPE Home > Th. List > Mathboxes > dig2bits | Structured version Visualization version GIF version |
Description: The 𝐾 th digit of a nonnegative integer 𝑁 in a binary system is its 𝐾 th bit. (Contributed by AV, 24-May-2020.) |
Ref | Expression |
---|---|
dig2bits | ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → ((𝐾(digit‘2)𝑁) = 1 ↔ 𝐾 ∈ (bits‘𝑁))) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nn0re 11652 | . . . . . 6 ⊢ (𝑁 ∈ ℕ0 → 𝑁 ∈ ℝ) | |
2 | 1 | adantr 474 | . . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 𝑁 ∈ ℝ) |
3 | 2re 11449 | . . . . . . 7 ⊢ 2 ∈ ℝ | |
4 | 3 | a1i 11 | . . . . . 6 ⊢ (𝑁 ∈ ℕ0 → 2 ∈ ℝ) |
5 | reexpcl 13195 | . . . . . 6 ⊢ ((2 ∈ ℝ ∧ 𝐾 ∈ ℕ0) → (2↑𝐾) ∈ ℝ) | |
6 | 4, 5 | sylan 575 | . . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (2↑𝐾) ∈ ℝ) |
7 | 2cnd 11453 | . . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 2 ∈ ℂ) | |
8 | 2ne0 11486 | . . . . . . 7 ⊢ 2 ≠ 0 | |
9 | 8 | a1i 11 | . . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 2 ≠ 0) |
10 | nn0z 11752 | . . . . . . 7 ⊢ (𝐾 ∈ ℕ0 → 𝐾 ∈ ℤ) | |
11 | 10 | adantl 475 | . . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 𝐾 ∈ ℤ) |
12 | 7, 9, 11 | expne0d 13333 | . . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (2↑𝐾) ≠ 0) |
13 | 2, 6, 12 | redivcld 11203 | . . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (𝑁 / (2↑𝐾)) ∈ ℝ) |
14 | 13 | flcld 12918 | . . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (⌊‘(𝑁 / (2↑𝐾))) ∈ ℤ) |
15 | mod2eq1n2dvds 15475 | . . 3 ⊢ ((⌊‘(𝑁 / (2↑𝐾))) ∈ ℤ → (((⌊‘(𝑁 / (2↑𝐾))) mod 2) = 1 ↔ ¬ 2 ∥ (⌊‘(𝑁 / (2↑𝐾))))) | |
16 | 14, 15 | syl 17 | . 2 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (((⌊‘(𝑁 / (2↑𝐾))) mod 2) = 1 ↔ ¬ 2 ∥ (⌊‘(𝑁 / (2↑𝐾))))) |
17 | 2nn 11448 | . . . . 5 ⊢ 2 ∈ ℕ | |
18 | 17 | a1i 11 | . . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 2 ∈ ℕ) |
19 | simpr 479 | . . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 𝐾 ∈ ℕ0) | |
20 | nn0rp0 12593 | . . . . 5 ⊢ (𝑁 ∈ ℕ0 → 𝑁 ∈ (0[,)+∞)) | |
21 | 20 | adantr 474 | . . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → 𝑁 ∈ (0[,)+∞)) |
22 | nn0digval 43409 | . . . 4 ⊢ ((2 ∈ ℕ ∧ 𝐾 ∈ ℕ0 ∧ 𝑁 ∈ (0[,)+∞)) → (𝐾(digit‘2)𝑁) = ((⌊‘(𝑁 / (2↑𝐾))) mod 2)) | |
23 | 18, 19, 21, 22 | syl3anc 1439 | . . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (𝐾(digit‘2)𝑁) = ((⌊‘(𝑁 / (2↑𝐾))) mod 2)) |
24 | 23 | eqeq1d 2780 | . 2 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → ((𝐾(digit‘2)𝑁) = 1 ↔ ((⌊‘(𝑁 / (2↑𝐾))) mod 2) = 1)) |
25 | nn0z 11752 | . . 3 ⊢ (𝑁 ∈ ℕ0 → 𝑁 ∈ ℤ) | |
26 | bitsval2 15553 | . . 3 ⊢ ((𝑁 ∈ ℤ ∧ 𝐾 ∈ ℕ0) → (𝐾 ∈ (bits‘𝑁) ↔ ¬ 2 ∥ (⌊‘(𝑁 / (2↑𝐾))))) | |
27 | 25, 26 | sylan 575 | . 2 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → (𝐾 ∈ (bits‘𝑁) ↔ ¬ 2 ∥ (⌊‘(𝑁 / (2↑𝐾))))) |
28 | 16, 24, 27 | 3bitr4d 303 | 1 ⊢ ((𝑁 ∈ ℕ0 ∧ 𝐾 ∈ ℕ0) → ((𝐾(digit‘2)𝑁) = 1 ↔ 𝐾 ∈ (bits‘𝑁))) |
Colors of variables: wff setvar class |
Syntax hints: ¬ wn 3 → wi 4 ↔ wb 198 ∧ wa 386 = wceq 1601 ∈ wcel 2107 ≠ wne 2969 class class class wbr 4886 ‘cfv 6135 (class class class)co 6922 ℝcr 10271 0cc0 10272 1c1 10273 +∞cpnf 10408 / cdiv 11032 ℕcn 11374 2c2 11430 ℕ0cn0 11642 ℤcz 11728 [,)cico 12489 ⌊cfl 12910 mod cmo 12987 ↑cexp 13178 ∥ cdvds 15387 bitscbits 15547 digitcdig 43404 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1839 ax-4 1853 ax-5 1953 ax-6 2021 ax-7 2055 ax-8 2109 ax-9 2116 ax-10 2135 ax-11 2150 ax-12 2163 ax-13 2334 ax-ext 2754 ax-rep 5006 ax-sep 5017 ax-nul 5025 ax-pow 5077 ax-pr 5138 ax-un 7226 ax-cnex 10328 ax-resscn 10329 ax-1cn 10330 ax-icn 10331 ax-addcl 10332 ax-addrcl 10333 ax-mulcl 10334 ax-mulrcl 10335 ax-mulcom 10336 ax-addass 10337 ax-mulass 10338 ax-distr 10339 ax-i2m1 10340 ax-1ne0 10341 ax-1rid 10342 ax-rnegex 10343 ax-rrecex 10344 ax-cnre 10345 ax-pre-lttri 10346 ax-pre-lttrn 10347 ax-pre-ltadd 10348 ax-pre-mulgt0 10349 ax-pre-sup 10350 |
This theorem depends on definitions: df-bi 199 df-an 387 df-or 837 df-3or 1072 df-3an 1073 df-tru 1605 df-ex 1824 df-nf 1828 df-sb 2012 df-mo 2551 df-eu 2587 df-clab 2764 df-cleq 2770 df-clel 2774 df-nfc 2921 df-ne 2970 df-nel 3076 df-ral 3095 df-rex 3096 df-reu 3097 df-rmo 3098 df-rab 3099 df-v 3400 df-sbc 3653 df-csb 3752 df-dif 3795 df-un 3797 df-in 3799 df-ss 3806 df-pss 3808 df-nul 4142 df-if 4308 df-pw 4381 df-sn 4399 df-pr 4401 df-tp 4403 df-op 4405 df-uni 4672 df-iun 4755 df-br 4887 df-opab 4949 df-mpt 4966 df-tr 4988 df-id 5261 df-eprel 5266 df-po 5274 df-so 5275 df-fr 5314 df-we 5316 df-xp 5361 df-rel 5362 df-cnv 5363 df-co 5364 df-dm 5365 df-rn 5366 df-res 5367 df-ima 5368 df-pred 5933 df-ord 5979 df-on 5980 df-lim 5981 df-suc 5982 df-iota 6099 df-fun 6137 df-fn 6138 df-f 6139 df-f1 6140 df-fo 6141 df-f1o 6142 df-fv 6143 df-riota 6883 df-ov 6925 df-oprab 6926 df-mpt2 6927 df-om 7344 df-1st 7445 df-2nd 7446 df-wrecs 7689 df-recs 7751 df-rdg 7789 df-er 8026 df-en 8242 df-dom 8243 df-sdom 8244 df-sup 8636 df-inf 8637 df-pnf 10413 df-mnf 10414 df-xr 10415 df-ltxr 10416 df-le 10417 df-sub 10608 df-neg 10609 df-div 11033 df-nn 11375 df-2 11438 df-n0 11643 df-z 11729 df-uz 11993 df-rp 12138 df-ico 12493 df-fl 12912 df-mod 12988 df-seq 13120 df-exp 13179 df-dvds 15388 df-bits 15550 df-dig 43405 |
This theorem is referenced by: (None) |
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