%I #14 Jan 13 2020 18:27:33
%S 1,4,9,16,25,30,36,49,64,81,90,100,108,120,121,143,144,154,169,182,
%T 196,225,256,289,306,324,340,360,361,399,400,408,418,432,441,462,475,
%U 480,484,494,525,529,532,546,550,572,576,588,616,621,625,650,667,676,690
%N Positive numbers of the form u * v where the binary representations of u and of v have the same number of 0's and the same number of 1's.
%C In other words, the terms of this sequence are squares or the products of two binary anagrams.
%C Leading zeros are ignored.
%C If m belongs to the sequence, then 4*m also belongs to the sequence.
%H Rémy Sigrist, <a href="/A331219/b331219.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A331266(n) * A331267(n).
%e The binary representations of 5 and 6 are "101" and "110", respectively.
%e So 5 and 6 are binary anagrams, and 30 = 5*6 belongs to the sequence.
%o (PARI) is(n, base=2) = fordiv (n,d, if (vecsort(digits(d,base))==vecsort(digits(n/d,base)), return (1))); return (0)
%Y Cf. A331220 (ternary analog), A331221 (decimal analog), A331266, A331267.
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Jan 12 2020
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