Theorem psrbasfsupp 33769

Description: Rewrite a finite support for nonnegative integers : For functions mapping a set 𝐼 to the nonnegative integers, having finite support can also be written as having a finite preimage of the positive integers. The latter expression is used for example in psrbas 21974, but with the former expression, theorems about finite support can be used more directly. (Contributed by Thierry Arnoux, 10-Jan-2026.)

Hypothesis

Ref	Expression
psrbasfsupp.d	⊢ 𝐷 = {𝑓 ∈ (ℕ0 ↑m 𝐼) ∣ 𝑓 finSupp 0}

Assertion

Ref	Expression
psrbasfsupp	⊢ 𝐷 = {𝑓 ∈ (ℕ0 ↑m 𝐼) ∣ (◡𝑓 “ ℕ) ∈ Fin}

Proof of Theorem psrbasfsupp

Step	Hyp	Ref	Expression
1		psrbasfsupp.d	. 2 ⊢ 𝐷 = {𝑓 ∈ (ℕ0 ↑m 𝐼) ∣ 𝑓 finSupp 0}
2		0nn0 12490	. . . . 5 ⊢ 0 ∈ ℕ0
3		isfsupp 9305	. . . . 5 ⊢ ((𝑓 ∈ (ℕ0 ↑m 𝐼) ∧ 0 ∈ ℕ0) → (𝑓 finSupp 0 ↔ (Fun 𝑓 ∧ (𝑓 supp 0) ∈ Fin)))
4	2, 3	mpan2 701	. . . 4 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (𝑓 finSupp 0 ↔ (Fun 𝑓 ∧ (𝑓 supp 0) ∈ Fin)))
5		elmapfun 8841	. . . . 5 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → Fun 𝑓)
6	5	biantrurd 540	. . . 4 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → ((𝑓 supp 0) ∈ Fin ↔ (Fun 𝑓 ∧ (𝑓 supp 0) ∈ Fin)))
7		dfn2 12488	. . . . . . . . . 10 ⊢ ℕ = (ℕ0 ∖ {0})
8	7	ineq2i 4167	. . . . . . . . 9 ⊢ (ran 𝑓 ∩ ℕ) = (ran 𝑓 ∩ (ℕ0 ∖ {0}))
9		incom 4159	. . . . . . . . 9 ⊢ (ran 𝑓 ∩ ℕ) = (ℕ ∩ ran 𝑓)
10		indif2 4231	. . . . . . . . 9 ⊢ (ran 𝑓 ∩ (ℕ0 ∖ {0})) = ((ran 𝑓 ∩ ℕ0) ∖ {0})
11	8, 9, 10	3eqtr3i 2792	. . . . . . . 8 ⊢ (ℕ ∩ ran 𝑓) = ((ran 𝑓 ∩ ℕ0) ∖ {0})
12		elmapi 8824	. . . . . . . . . . 11 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → 𝑓:𝐼⟶ℕ0)
13	12	frnd 6695	. . . . . . . . . 10 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → ran 𝑓 ⊆ ℕ0)
14		dfss2 3920	. . . . . . . . . 10 ⊢ (ran 𝑓 ⊆ ℕ0 ↔ (ran 𝑓 ∩ ℕ0) = ran 𝑓)
15	13, 14	sylib 220	. . . . . . . . 9 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (ran 𝑓 ∩ ℕ0) = ran 𝑓)
16	15	difeq1d 4077	. . . . . . . 8 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → ((ran 𝑓 ∩ ℕ0) ∖ {0}) = (ran 𝑓 ∖ {0}))
17	11, 16	eqtrid 2808	. . . . . . 7 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (ℕ ∩ ran 𝑓) = (ran 𝑓 ∖ {0}))
18	17	imaeq2d 6045	. . . . . 6 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (◡𝑓 “ (ℕ ∩ ran 𝑓)) = (◡𝑓 “ (ran 𝑓 ∖ {0})))
19		fimacnvinrn 7047	. . . . . . 7 ⊢ (Fun 𝑓 → (◡𝑓 “ ℕ) = (◡𝑓 “ (ℕ ∩ ran 𝑓)))
20	5, 19	syl 17	. . . . . 6 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (◡𝑓 “ ℕ) = (◡𝑓 “ (ℕ ∩ ran 𝑓)))
21		id 22	. . . . . . 7 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → 𝑓 ∈ (ℕ0 ↑m 𝐼))
22	2	a1i 11	. . . . . . 7 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → 0 ∈ ℕ0)
23		supppreima 32854	. . . . . . 7 ⊢ ((Fun 𝑓 ∧ 𝑓 ∈ (ℕ0 ↑m 𝐼) ∧ 0 ∈ ℕ0) → (𝑓 supp 0) = (◡𝑓 “ (ran 𝑓 ∖ {0})))
24	5, 21, 22, 23	syl3anc 1389	. . . . . 6 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (𝑓 supp 0) = (◡𝑓 “ (ran 𝑓 ∖ {0})))
25	18, 20, 24	3eqtr4rd 2807	. . . . 5 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (𝑓 supp 0) = (◡𝑓 “ ℕ))
26	25	eleq1d 2846	. . . 4 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → ((𝑓 supp 0) ∈ Fin ↔ (◡𝑓 “ ℕ) ∈ Fin))
27	4, 6, 26	3bitr2d 309	. . 3 ⊢ (𝑓 ∈ (ℕ0 ↑m 𝐼) → (𝑓 finSupp 0 ↔ (◡𝑓 “ ℕ) ∈ Fin))
28	27	rabbiia 3417	. 2 ⊢ {𝑓 ∈ (ℕ0 ↑m 𝐼) ∣ 𝑓 finSupp 0} = {𝑓 ∈ (ℕ0 ↑m 𝐼) ∣ (◡𝑓 “ ℕ) ∈ Fin}
29	1, 28	eqtri 2784	1 ⊢ 𝐷 = {𝑓 ∈ (ℕ0 ↑m 𝐼) ∣ (◡𝑓 “ ℕ) ∈ Fin}

Syntax hints:   ↔ wb 208   ∧ wa 399   = wceq 1559   ∈ wcel 2141  {crab 3413   ∖ cdif 3899   ∩ cin 3901   ⊆ wss 3902  {csn 4579   class class class wbr 5097  ^◡ccnv 5642  ran crn 5644   “ cima 5646  Fun wfun 6510  (class class class)co 7391   supp csupp 8134   ↑_m cmap 8802  Fincfn 8921   finSupp cfsupp 9301  0cc0 11067  ℕcn 12204  ℕ₀cn0 12475

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1814  ax-4 1828  ax-5 1929  ax-6 1986  ax-7 2027  ax-8 2143  ax-9 2151  ax-10 2174  ax-11 2190  ax-12 2211  ax-ext 2733  ax-sep 5243  ax-nul 5253  ax-pow 5319  ax-pr 5387  ax-un 7713  ax-resscn 11124  ax-1cn 11125  ax-icn 11126  ax-addcl 11127  ax-addrcl 11128  ax-mulcl 11129  ax-mulrcl 11130  ax-mulcom 11131  ax-addass 11132  ax-mulass 11133  ax-distr 11134  ax-i2m1 11135  ax-1ne0 11136  ax-1rid 11137  ax-rnegex 11138  ax-rrecex 11139  ax-cnre 11140  ax-pre-lttri 11141  ax-pre-lttrn 11142  ax-pre-ltadd 11143

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3or 1098  df-3an 1099  df-tru 1562  df-fal 1572  df-ex 1799  df-nf 1803  df-sb 2090  df-mo 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-nel 3061  df-ral 3076  df-rex 3086  df-reu 3367  df-rab 3414  df-v 3455  df-sbc 3743  df-csb 3851  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-pss 3922  df-nul 4284  df-if 4478  df-pw 4554  df-sn 4580  df-pr 4582  df-op 4586  df-uni 4863  df-iun 4948  df-br 5098  df-opab 5160  df-mpt 5179  df-tr 5205  df-id 5538  df-eprel 5543  df-po 5551  df-so 5552  df-fr 5596  df-we 5598  df-xp 5649  df-rel 5650  df-cnv 5651  df-co 5652  df-dm 5653  df-rn 5654  df-res 5655  df-ima 5656  df-pred 6283  df-ord 6344  df-on 6345  df-lim 6346  df-suc 6347  df-iota 6472  df-fun 6518  df-fn 6519  df-f 6520  df-f1 6521  df-fo 6522  df-f1o 6523  df-fv 6524  df-ov 7394  df-oprab 7395  df-mpo 7396  df-om 7842  df-1st 7965  df-2nd 7966  df-supp 8135  df-frecs 8256  df-wrecs 8287  df-recs 8336  df-rdg 8375  df-er 8672  df-map 8804  df-en 8922  df-dom 8923  df-sdom 8924  df-fsupp 9302  df-pnf 11212  df-mnf 11213  df-xr 11214  df-ltxr 11215  df-le 11216  df-nn 12205  df-n0 12476

This theorem is referenced by:  0mplrim  33772  selvply1rhmlema  33776  selvply1rhmlemb  33777  selvply1rhmlem1  33778  selvply1rhmlem2  33779  selvply1rhmlem4  33781  selvply1rhm0  33784  extvfvvcl  33793  extvfvcl  33794  mplmulmvr  33797  evlextv  33800  mplvrpmfgalem  33802  mplvrpmga  33803  mplvrpmmhm  33804  mplvrpmrhm  33805  psrgsum  33806  psrmon  33807  psrmonmul  33808  psrmonmul2  33809  psrmonprod  33810  mplgsum  33811  mplmonprod  33812  issply  33819  esplyfval0  33822  esplyfval2  33823  esplympl  33825  esplymhp  33826  esplyfval3  33830  esplyfval1  33831  esplyfvaln  33832  esplyind  33833  vieta  33838