A241720 Number of compositions of n into distinct parts with exactly one descent.

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

Author

Alois P. Heinz, Apr 27 2014

Keywords

• nonn

Examples

			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].
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 3..1000

Crossrefs

Column k=1 of A241719.