Number of set partitions of [n] such that the difference between each element and its index (in the partition) is a multiple of three.

A274860

Number of set partitions of [n] such that the difference between each element and its index (in the partition) is a multiple of three.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =16a(6) =32a(7) =68a(8) =144a(9) =304a(10) =692a(11) =1580a(12) =3602a(13) =8976a(14) =22552a(15) =56850a(16) =157740a(17) =442101a(18) =1249124a(19) =3868420a(20) =12082568a(21) =38117838a(22) =130394944a(23) =448733361a(24) =1559590892a(25) =5817284716a(26) =21787658638a(27) =82365982741a(28) =331668252301

External references