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A326307 a(n) is the index of n in the ordered list of the numbers with the same digits as n.

%I A326307 #36 Jan 30 2025 17:17:56
%S A326307 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,2,2,1,
%T A326307 1,1,1,1,1,1,1,2,2,2,1,1,1,1,1,1,1,2,2,2,2,1,1,1,1,1,1,2,2,2,2,2,1,1,
%U A326307 1,1,1,2,2,2,2,2,2,1,1,1,1,2,2,2,2,2,2,2
%N A326307 a(n) is the index of n in the ordered list of the numbers with the same digits as n.
%C A326307 Ordinal transform of A328447.
%H A326307 David A. Corneth, <a href="/A326307/b326307.txt">Table of n, a(n) for n = 0..9999</a>
%H A326307 David A. Corneth, <a href="/A326307/a326307.gp.txt">PARI program</a>
%F A326307 a(A179239(n)) = 1.
%F A326307 a(10+n) = A007953(9*n)/9 (A007953 = sum of digits) for 0 < n < 91, but a(101) = 1 while A007953(9*91)/9 = 2. - _M. F. Hasler_, May 19 2021
%e A326307 a(321) = 6 as 321 is the sixth number made of the digits [1, 2, 3]. The five smaller numbers having these digits are 123, 132, 213, 231, 312.
%o A326307 (PARI) see Corneth link
%o A326307 (PARI) { o = vector(100); for (n=0, 87, print1 (o[1+fromdigits(vecsort(digits(n,base=10),,4),base)]++ ", ")) } \\ _Rémy Sigrist_, Oct 17 2019
%o A326307 (PARI) A326307(n,D=Vecsmall(digits(n)),c=1)={forperm(vecsort(D),d, d==D&&break; d[1]&&c++);c} \\ _M. F. Hasler_, May 19 2021
%o A326307 (Python)
%o A326307 from collections import Counter
%o A326307 from itertools import count, islice
%o A326307 def agen(): # generator of terms
%o A326307     digmultisetcount = Counter()
%o A326307     for n in count(0):
%o A326307         key = "".join(sorted(str(n)))
%o A326307         digmultisetcount[key] += 1
%o A326307         yield digmultisetcount[key]
%o A326307 print(list(islice(agen(), 88))) # _Michael S. Branicky_, Jan 30 2025
%Y A326307 Cf. A179239, A254524, A328447.
%K A326307 nonn,base,easy,look
%O A326307 0,22
%A A326307 _David A. Corneth_, Oct 17 2019
%E A326307 Edited by _N. J. A. Sloane_, Oct 24 2019