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%I #13 Nov 29 2014 02:53:31
%S 0,0,1,4,14,47,154,514,1719,5901,20339,70137,245473,854033,3012779,
%T 10708332
%N a(0) = 0. a(n) is the number of distinct sums formed by [a(0), ... a(n-1)] + [a(0), ... a(n-1)] + ... + [a(0), ... a(n-1)], where [a(0), ... a(n-1)] is repeated n times.
%e a(1) is the number of sums made from [0]. No sums can be made from this because 0 is not being added to anything. So a(1) = 0.
%e a(2) is the number of sums made from [0,0] + [0,0]. The only possible sum is 0, so a(2) = 1.
%e a(3) is the number of sums made from [0,0,1] + [0,0,1] + [0,0,1]. The possible sums are 0, 1, 2, and 3, so a(3) = 4.
%e a(4) is the number of sums made from [0,0,1,4] + [0,0,1,4] + [0,0,1,4] + [0,0,1,4]. There are 14 different possible sums so a(4) = 14.
%K nonn,more,hard
%O 0,4
%A _Derek Orr_, Nov 26 2014
%E a(11)-a(15) from _Hiroaki Yamanouchi_, Nov 29 2014
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