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%I #12 Mar 12 2017 15:12:17
%S 1,2,5,20,170,3650,298132,159632503
%N Number of nondecreasing sequences of n positive integers with reciprocals adding up to an integer.
%F a(n) = A156869(n, 1) + ... + A156869(n, n).
%e For n = 3, the A156871(3) = 5 sequences are (1, 1, 1), (1, 2, 2), (2, 3, 6), (2, 4, 4) and (3, 3, 3) because 1/1 + 1/1 + 1/1 = 3, 1/1 + 1/2 + 1/2 = 2 and 1/2 + 1/3 + 1/6 = 1/2 + 1/4 + 1/4 = 1/3 + 1/3 + 1/3 = 1.
%Y Cf. A002966, A156869, A280517, A280518.
%K more,nonn
%O 1,2
%A _Jens Voß_, Feb 17 2009
%E a(7), a(8) from _Max Alekseyev_, Jul 27 2009
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