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A241720
Number of compositions of n into distinct parts with exactly one descent.
2
1, 1, 2, 6, 7, 11, 16, 31, 36, 55, 71, 101, 147, 188, 245, 327, 421, 540, 732, 899, 1154, 1445, 1831, 2253, 2846, 3545, 4352, 5352, 6576, 7993, 9778, 11826, 14314, 17430, 20866, 25076, 30043, 35974, 42776, 51053, 60463, 71772, 85094, 100370, 118155, 139331
OFFSET
3,3
LINKS
EXAMPLE
a(3) = 1: [2,1].
a(4) = 1: [3,1].
a(5) = 2: [3,2], [4,1].
a(6) = 6: [4,2], [5,1], [2,3,1], [3,1,2], [1,3,2], [2,1,3].
a(7) = 7: [4,3], [5,2], [6,1], [2,4,1], [4,1,2], [1,4,2], [2,1,4].
a(8) = 11: [6,2], [5,3], [7,1], [1,4,3], [3,1,4], [2,1,5], [3,4,1], [2,5,1], [5,1,2], [1,5,2], [4,1,3].
a(9) = 16: [5,4], [8,1], [7,2], [6,3], [2,6,1], [3,5,1], [6,1,2], [1,6,2], [2,1,6], [3,4,2], [4,2,3], [5,1,3], [2,4,3], [1,5,3], [3,2,4], [3,1,5].
CROSSREFS
Column k=1 of A241719.
Sequence in context: A088227 A231500 A174000 * A224082 A051678 A079906
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Apr 27 2014
STATUS
approved