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%I #10 Jan 13 2020 18:26:18
%S 1,2,3,4,5,5,6,7,8,9,10,10,11,12,11,13,14,11,14,15,11,16,15,17,14,15,
%T 18,16,19,17,19,20,17,21,20,22,23,23,24,25,26,27,28,28,29,30,29,31,28,
%U 32,30,32,33,31,34,31,32,35,34,36,29,32,37,34,37,38,32,33
%N a(n) is the least divisor u of A331220(n) such that the ternary representations of u and of A331220(n)/u have the same number of digits d for d = 0..2.
%H Rémy Sigrist, <a href="/A331268/b331268.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) * A331269(n) = A331220(n).
%o (PARI) b=3; k=68; for (n=1, oo, fordiv (n, u, if (vecsort(digits(u,b))==vecsort(digits(n/u,b)), print1 (u", "); break (if (k--, 1, 2)))))
%Y Cf. A331220, A331269.
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Jan 13 2020
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