Number of set partitions of [n] such that i-j is a multiple of four for all i,j belonging to the same block.
A275071
Number of set partitions of [n] such that i-j is a multiple of four for all i,j belonging to the same block.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =2a(6) =4a(7) =8a(8) =16a(9) =40a(10) =100a(11) =250a(12) =625a(13) =1875a(14) =5625a(15) =16875a(16) =50625a(17) =175500a(18) =608400a(19) =2109120a(20) =7311616a(21) =28543424a(22) =111429136a(23) =435002204a(24) =1698181681a(25) =7336479479a(26) =31695036961a(27) =136928804999a(28) =591559418641
External references
- oeis: A275071