A214275 Number of compositions of n where the difference between largest and smallest parts equals 6 and adjacent parts are unequal.
0, 2, 1, 8, 12, 23, 56, 100, 191, 370, 703, 1280, 2409, 4437, 8076, 14821, 26895, 48760, 88102, 158831, 285490, 512395, 917768, 1640448, 2928758, 5220037, 9291968, 16519618, 29335963, 52038382, 92218708, 163272053, 288813272, 510469514, 901536574, 1591035005
Offset: 7
Keywords
Examples
a(8) = 2: [7,1], [1,7]. a(9) = 1: [1,7,1]. a(10) = 8: [8,2], [7,2,1], [7,1,2], [2,8], [2,7,1], [2,1,7], [1,7,2], [1,2,7]. a(11) = 12: [7,3,1], [7,1,3], [7,1,2,1], [3,7,1], [3,1,7], [2,1,7,1], [1,7,3], [1,7,2,1], [1,7,1,2], [1,3,7], [1,2,7,1], [1,2,1,7].
Links
- Alois P. Heinz, Table of n, a(n) for n = 7..2000
Crossrefs
Column k=6 of A214269.