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A247210
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.
0
0, 0, 1, 4, 14, 47, 154, 514, 1719, 5901, 20339, 70137, 245473, 854033, 3012779, 10708332
OFFSET
0,4
EXAMPLE
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.
a(2) is the number of sums made from [0,0] + [0,0]. The only possible sum is 0, so a(2) = 1.
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.
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.
CROSSREFS
Sequence in context: A192877 A263622 A104487 * A094789 A273714 A082574
KEYWORD
nonn,more,hard
AUTHOR
Derek Orr, Nov 26 2014
EXTENSIONS
a(11)-a(15) from Hiroaki Yamanouchi, Nov 29 2014
STATUS
approved