Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-n,...,n}.
A239561
Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-n,...,n}.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =8a(6) =16a(7) =31a(8) =63a(9) =125a(10) =252a(11) =504a(12) =1013a(13) =2027a(14) =4069a(15) =8141a(16) =16318a(17) =32650a(18) =65381a(19) =130801a(20) =261791a(21) =523677a(22) =1047780a(23) =2095796a(24) =4192533a(25) =8385623a(26) =16773321a(27) =33547917a(28) =67100362a(29) =134203614
External references
- oeis: A239561