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A356369 Numbers such that each digit "d" occurs d times, for every digit from 1 to the largest digit.

%I A356369 #45 Nov 12 2022 10:21:12
%S A356369 1,122,212,221,122333,123233,123323,123332,132233,132323,132332,
%T A356369 133223,133232,133322,212333,213233,213323,213332,221333,223133,
%U A356369 223313,223331,231233,231323,231332,232133,232313,232331,233123,233132,233213,233231,233312,233321,312233,312323
%N A356369 Numbers such that each digit "d" occurs d times, for every digit from 1 to the largest digit.
%C A356369 A version of self-describing integers (cf. A105776).
%C A356369 The sequence is finite.
%C A356369 The last term is 999999999888888887777777666666555554444333221.
%C A356369 This sequence contains Sum_{m = 1..9} Product_{k = 1..m} binomial( k*(k+1)/2, k) = 65191584768311709900058498136517664 terms. - _Thomas Scheuerle_ and _David A. Corneth_, Oct 17 2022
%H A356369 Michael S. Branicky, <a href="/A356369/b356369.txt">Table of n, a(n) for n = 1..10000</a>
%e A356369 213323 is a term because the digit 1 occurs once, the digit 2 twice and 3 three times. Every digit from 1 to 3 is present.
%o A356369 (Python)
%o A356369 from itertools import islice
%o A356369 from sympy.utilities.iterables import multiset_permutations
%o A356369 def agen():
%o A356369     for m in range(1, 10):
%o A356369         s = "".join(str(k)*k for k in range(1, m+1))
%o A356369         yield from (int("".join(p)) for p in multiset_permutations(s))
%o A356369 print(list(islice(agen(), 65))) # _Michael S. Branicky_, Oct 17 2022
%Y A356369 Cf. A105776, A108571, A247700.
%K A356369 nonn,base,fini
%O A356369 1,2
%A A356369 _Marc Morgenegg_, Oct 17 2022
%E A356369 Corrected by and more terms from _David A. Corneth_, Oct 17 2022