Triangle read by rows: T(n,k) is the number of nilpotent subpermutations on an n-set, each of nilpotency index less than or equal to k.

A261764

Triangle read by rows: T(n,k) is the number of nilpotent subpermutations on an n-set, each of nilpotency index less than or equal to k.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =0a(4) =1a(5) =3a(6) =0a(7) =1a(8) =7a(9) =13a(10) =0a(11) =1a(12) =25a(13) =49a(14) =73a(15) =0a(16) =1a(17) =81a(18) =261a(19) =381a(20) =501a(21) =0a(22) =1a(23) =331a(24) =1531a(25) =2611a(26) =3331a(27) =4051a(28) =0a(29) =1

External references