Number of set partitions of [n] into exactly seven blocks such that all odd elements are in blocks with an odd index and all even elements are in blocks with an even index.

A274871

Number of set partitions of [n] into exactly seven blocks such that all odd elements are in blocks with an odd index and all even elements are in blocks with an even index.

Terms

    a(0) =1a(1) =3a(2) =34a(3) =102a(4) =719a(5) =2157a(6) =12260a(7) =36780a(8) =185457a(9) =556371a(10) =2607078a(11) =7821234a(12) =34949443a(13) =104848329a(14) =453798280a(15) =1361394840a(16) =5763944693a(17) =17291834079a(18) =72085646282a(19) =216256938846a(20) =891613471047

External references