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A030480 Primes with property that when squared all even digits occur together and all odd digits occur together.

%I A030480 #12 Oct 18 2023 10:04:29
%S A030480 2,3,5,7,17,29,47,53,67,79,83,149,151,157,257,283,457,653,683,907,
%T A030480 1429,1571,1693,1699,2017,2459,2467,2543,2609,2617,2843,2879,2909,
%U A030480 2971,4759,5101,5179,5333,6653,6803,6947,6949,7759,8297,9091,9103
%N A030480 Primes with property that when squared all even digits occur together and all odd digits occur together.
%C A030480 Primes whose squares have at most one odd digit. - _Robert Israel_, Oct 17 2023
%H A030480 Robert Israel, <a href="/A030480/b030480.txt">Table of n, a(n) for n = 1..1000</a>
%p A030480 filter:= proc(n) local L;
%p A030480   if not isprime(n) then return false fi;
%p A030480   convert(convert(n^2,base,10)[2..-1] mod 2,set) = {0};
%p A030480 end proc:
%p A030480 filter(2):= true: filter(3):= true:
%p A030480 select(filter, [2,seq(i,i=3..10000,2)]); # _Robert Israel_, Oct 17 2023
%t A030480 With[{upto=10^4},Select[Prime[Range[upto]],Count[IntegerDigits[#^2],_?OddQ]<2&]] (* _Paolo Xausa_, Oct 18 2023 *)
%Y A030480 Cf. A030475, A030476.
%K A030480 nonn,base
%O A030480 1,1
%A A030480 _Patrick De Geest_
%E A030480 Offset changed by _Robert Israel_, Oct 17 2023