cp's OEIS Frontend

A235724 Squares which have one or more occurrences of exactly nine different digits.

%I A235724 #35 May 24 2022 12:55:25
%S A235724 102495376,102576384,102738496,104325796,105637284,139854276,
%T A235724 152843769,157326849,158306724,158407396,172843609,176039824,
%U A235724 176305284,178035649,180472356,183467025,187635204,198753604,208571364,215384976,217356049,218034756,235714609
%N A235724 Squares which have one or more occurrences of exactly nine different digits.
%C A235724 The first term having a repeated digit is 1005397264.
%C A235724 The smallest penholodigital square is a(6) = A036744(1) = 139854276 and the largest one is a(83) = A036744(30) = 923187456 (see Penguin references). - _Bernard Schott_, Feb 07 2022
%D A235724 David Wells, The Penguin Dictionary of Curious and Interesting Numbers (Revised Edition), Penguin Books, 1997, entry 139854276, page 184 and entry 923187456, page 186.
%H A235724 Michael S. Branicky, <a href="/A235724/b235724.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Colin Barker)
%F A235724 a(n) = A054037(n)^2.
%e A235724 102495376 is in the sequence because 102495376 = 10124^2 and 102495376 contains exactly nine different digits: 0, 1, 2, 3, 4, 5, 6, 7 and 9.
%o A235724 (PARI) s=[]; for(n=1, 100000, if(#vecsort(eval(Vec(Str(n^2))),,8)==9, s=concat(s, n^2))); s
%o A235724 (Python)
%o A235724 from itertools import count, islice
%o A235724 def agen(): yield from (r*r for r in count(10**4) if len(set(str(r*r)))==9)
%o A235724 print(list(islice(agen(), 23))) # _Michael S. Branicky_, May 24 2022
%Y A235724 Cf. A054037.
%Y A235724 Cf. A235717-A235723, A225218.
%Y A235724 A036744 is a subsequence.
%K A235724 nonn,base
%O A235724 1,1
%A A235724 _Colin Barker_, Jan 15 2014