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%I #4 Nov 02 2020 20:37:26
%S 0,1,2,0,3,0,4,0,1,1,5,0,6,2,3,1,7,2,8,3,4,5,9,0,2,6,1,4,10,0,11,0,7,
%T 8,9,0,12,10,11,1,13,1,14,5,6,12,15,0,3,7,13,8,16,2,14,3,15,16,17,0,
%U 18,17,9,0,18,2,19,10,19,3,20,0,21,20,11,12,21,4,22,1
%N Number of integers less than n with the same number of ordered factorizations as n.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/OrderedFactorization.html">Ordered Factorization</a>
%F a(n) = |{j < n : A074206(j) = A074206(n)}|.
%e a(14) = 2 because A074206(14) = 3 and also A074206(6) = A074206(10) = 3.
%t A074206[1] = 1; A074206[n_] := A074206[n] = A074206 /@ Most[Divisors[n]] // Total; Table[Length[Select[Range[n - 1], A074206[#] == A074206[n] &]], {n, 80}]
%Y Cf. A047983, A074206, A338568.
%K nonn
%O 1,3
%A _Ilya Gutkovskiy_, Nov 02 2020
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