A262196 Number of compositions of n such that the maximal distance between two identical parts equals three.
0, 1, 2, 6, 12, 25, 46, 88, 152, 267, 452, 764, 1260, 2049, 3314, 5272, 8354, 13077, 20366, 31302, 48048, 72849, 110244, 165354, 247194, 366703, 541802, 796066, 1164264, 1695201, 2457904, 3549244, 5104908, 7313739, 10437170, 14848936, 21041422, 29732907
Offset: 3
Keywords
Examples
a(4) = 1: 1111. a(5) = 2: 1121, 1211. a(6) = 6: 1131, 1221, 1311, 2112, 11112, 21111. a(7) = 12: 1141, 1231, 1321, 1411, 2122, 2212, 11113, 11212, 12112, 21121, 21211, 31111. a(8) = 25: 1151, 1241, 1331, 1421, 1511, 2132, 2222, 2312, 3113, 11114, 11213, 11312, 12113, 12122, 12212, 13112, 21131, 21221, 21311, 22121, 31121, 31211, 41111, 111122, 221111.
Crossrefs
Column k=3 of A262191.