Number of set partitions of [n] such that the difference between each element and its block index is a multiple of four.

A274837

Number of set partitions of [n] such that the difference between each element and its block index is a multiple of four.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =2a(6) =3a(7) =4a(8) =5a(9) =11a(10) =22a(11) =41a(12) =72a(13) =191a(14) =459a(15) =1033a(16) =2209a(17) =6696a(18) =18777a(19) =49526a(20) =124011a(21) =419203a(22) =1329966a(23) =4009931a(24) =11544970a(25) =43203329a(26) =152247581a(27) =511143253a(28) =1644388769a(29) =6707557342

External references