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%I #23 Sep 05 2023 16:46:27
%S 1,1,225,343396,44944,505575225,4666665969,77770707876,388888184881,
%T 9499999990849,1010101019780101025109910101001,
%U 1101191170117113111111301111961124,121214127521273511212121212512121241,135131321313113136131313387213513731136
%N Smallest square that contains exactly n occurrences of the string n.
%C Occurrences are counted without overlap, so 1111 has two occurrences of 11, not 3. - _Michael S. Branicky_, Aug 12 2023
%H Bert Dobbelaere, <a href="/A109688/b109688.txt">Table of n, a(n) for n = 0..15</a>
%e a(2)=225=15^2 since this is the first square that contains two 2's.
%t With[{sqs=Range[0,3100000]^2},Flatten[Table[Select[sqs,DigitCount[#,10,n] == n&,1],{n,9}]]] (* _Harvey P. Dale_, May 04 2012 *)
%o (Python)
%o from math import isqrt
%o def a(n):
%o sn = str(n)
%o k = 1 if n == 0 else isqrt(int(sn*n))
%o while True:
%o if str(k*k).count(sn) == n:
%o return k*k
%o k += 1
%o print([a(n) for n in range(10)]) # _Michael S. Branicky_, Feb 02 2022
%K nonn,base
%O 0,3
%A _Erich Friedman_, Aug 07 2005
%E Corrected and extended by _Giovanni Resta_, Apr 05 2006
%E a(10) and beyond from _Bert Dobbelaere_, Sep 05 2023
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