cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A235719 Squares which have one or more occurrences of exactly four different digits.

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%I A235719 #17 May 03 2018 12:05:19
%S A235719 1024,1089,1296,1369,1764,1849,1936,2304,2401,2601,2704,2809,2916,
%T A235719 3025,3249,3481,3721,4096,4356,4761,5041,5184,5329,5476,6084,6241,
%U A235719 6724,7056,7396,7569,7921,8649,9025,9216,9604,9801,10609,10816,11025,11236,12544,12996
%N A235719 Squares which have one or more occurrences of exactly four different digits.
%C A235719 The first term having a repeated digit is 10609.
%H A235719 Colin Barker, <a href="/A235719/b235719.txt">Table of n, a(n) for n = 1..1000</a>
%F A235719 a(n) = A054032(n)^2.
%e A235719 5329 is in the sequence because 5329 = 73^2 and 5329 contains exactly four different digits: 2, 3, 5 and 9.
%t A235719 Select[Range[150]^2,Length[Union[IntegerDigits[#]]]==4&] (* _Harvey P. Dale_, May 03 2018 *)
%o A235719 (PARI) s=[]; for(n=1, 300, if(#vecsort(eval(Vec(Str(n^2))),,8)==4, s=concat(s, n^2))); s
%Y A235719 Cf. A235717, A235718, A235720-A235724, A225218.
%K A235719 nonn,base
%O A235719 1,1
%A A235719 _Colin Barker_, Jan 15 2014