A238871 Number of weakly unimodal compositions of n with absolute difference of successive parts <= 1.
1, 1, 2, 4, 6, 10, 14, 21, 27, 40, 52, 70, 92, 124, 156, 206, 264, 335, 425, 539, 673, 847, 1052, 1300, 1611, 1990, 2433, 2977, 3638, 4420, 5367, 6496, 7829, 9439, 11341, 13590, 16270, 19425, 23135, 27525, 32697, 38745, 45844, 54168, 63875, 75247, 88493, 103892
Offset: 0
Keywords
Examples
The a(8) = 27 such compositions are: 01: [ 1 1 1 1 1 1 1 1 ] 02: [ 1 1 1 1 1 1 2 ] 03: [ 1 1 1 1 1 2 1 ] 04: [ 1 1 1 1 2 1 1 ] 05: [ 1 1 1 1 2 2 ] 06: [ 1 1 1 2 1 1 1 ] 07: [ 1 1 1 2 2 1 ] 08: [ 1 1 1 2 3 ] 09: [ 1 1 2 1 1 1 1 ] 10: [ 1 1 2 2 1 1 ] 11: [ 1 1 2 2 2 ] 12: [ 1 2 1 1 1 1 1 ] 13: [ 1 2 2 1 1 1 ] 14: [ 1 2 2 2 1 ] 15: [ 1 2 2 3 ] 16: [ 1 2 3 2 ] 17: [ 2 1 1 1 1 1 1 ] 18: [ 2 2 1 1 1 1 ] 19: [ 2 2 2 1 1 ] 20: [ 2 2 2 2 ] 21: [ 2 3 2 1 ] 22: [ 2 3 3 ] 23: [ 3 2 1 1 1 ] 24: [ 3 2 2 1 ] 25: [ 3 3 2 ] 26: [ 4 4 ] 27: [ 8 ]
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..1000