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%I #10 Jan 13 2020 18:27:09
%S 1,4,9,16,25,36,49,64,81,100,121,144,169,196,225,252,256,289,324,361,
%T 400,403,441,484,529,574,576,625,676,729,736,765,784,841,900,961,976,
%U 1008,1024,1089,1156,1207,1225,1296,1300,1369,1444,1458,1462,1521,1600
%N Positive numbers of the form u * v where the decimal representations of u and of v have the same number of digits d for d = 0..9.
%C In other words, the terms of this sequence are squares or the products of two decimal anagrams.
%C Leading zeros are ignored.
%C If m belongs to the sequence, then 100*m also belongs to the sequence.
%H Rémy Sigrist, <a href="/A331221/b331221.txt">Table of n, a(n) for n = 1..10000</a>
%e The numbers 12 and 21 are decimal anagrams, so 252 = 12*21 belongs to the sequence.
%o (PARI) is(n, base=10) = fordiv (n,d, if (vecsort(digits(d,base))==vecsort(digits(n/d,base)), return (1))); return (0)
%Y Cf. A331219 (binary analog), A331220 (ternary analog), A331270, A331271.
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Jan 12 2020
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