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%I #20 Oct 08 2017 18:40:10
%S 49,289,529,676,2209,2809,4489,5329,5776,5929,6889,7396,8836,9409,
%T 20449,24649,26569,27889,29929,30976,34969,37249,37636,38809,49729,
%U 54289,55696,59536,64009,65536,66049,67600,75076,76729,80089,82369,85849,94249,97969
%N Squares that are not divisible by any of their nonzero digits.
%C Intersection of A000290 and A038772.
%C The sequence is infinite since it contains all the terms (5*10^k+3)^2, k>0. - _Giovanni Resta_, Mar 12 2014
%H Colin Barker, <a href="/A239211/b239211.txt">Table of n, a(n) for n = 1..1000</a>
%e 2809 is in the sequence because 2809 is not divisible by 2, 8 or 9.
%t Select[Range[350]^2,NoneTrue[#/(IntegerDigits[#]/.(0->Nothing)), IntegerQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 08 2017 *)
%o (PARI) isOK(n) = my(v=vecsort(digits(n^2), , 8)); for(i=1+(v[1]==0), #v, if(n^2%v[i]==0, return(0))); 1
%o s=[]; for(n=1, 1000, if(isOK(n), s=concat(s, n^2))); s
%Y Cf. A239210, A239212, A239213.
%Y Cf. A000290, A038772.
%K nonn,base
%O 1,1
%A _Colin Barker_, Mar 12 2014
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