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%I #11 Jul 28 2021 04:16:30
%S 0,1,2,3,4,5,6,7,9,16,23,27,36,69,74,81,96,127,181,187,296,874,2327,
%T 2369,2723,2727,2763,3816,4589,5874,6563,6589,6727,8323,10181,12723,
%U 18163,18587,21236,21274,29236,29274,30127,43296,52361,78163,87616
%N Numbers k such that in k and k^2 the parity of digits alternates.
%H Giovanni Resta, <a href="/A030153/b030153.txt">Table of n, a(n) for n = 1..1226</a> (derived from A030154 b-file)
%t altQ[n_] := n < 10 || Union[Total /@ Partition[ Mod[ IntegerDigits@n, 2], 2, 1]] == {1}; Select[ Range[0, 10^5], altQ[#] && altQ[#^2] &] (* _Giovanni Resta_, Aug 16 2018 *)
%Y Cf. A030151, A030152, A030154, A030156, A030157, A030158.
%K nonn,base
%O 1,3
%A _Patrick De Geest_