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A280519 Triangle read by rows: T(n,k) = number of sequences of n positive integers with reciprocals adding up to k (k=1,2,...,n).

%I A280519 #7 Apr 28 2018 23:46:24
%S A280519 1,1,1,10,3,1,215,41,6,1,12231,1115,105,10,1,2025462,74862,3466,215,
%T A280519 15,1,1351857641,14294210,267281,8372,385,21,1,6255560531733,
%U A280519 10837663111,57646358,727049,17318,630,28,1
%N A280519 Triangle read by rows: T(n,k) = number of sequences of n positive integers with reciprocals adding up to k (k=1,2,...,n).
%e A280519 Triangle starts with:
%e A280519 n=1: 1
%e A280519 n=2: 1, 1
%e A280519 n=3: 10, 3, 1
%e A280519 n=4: 215, 41, 6, 1
%e A280519 n=5: 12231, 1115, 105, 10, 1
%e A280519 n=6: 2025462, 74862, 3466, 215, 15, 1
%e A280519 ...
%Y A280519 Cf. A280517 (row sums), A002967 (column k=1), A156869 (nondecreasing sequences), A280520 (increasing sequences).
%K A280519 nonn,tabl
%O A280519 1,4
%A A280519 _Max Alekseyev_, Jan 04 2017