Number of ways to select a set partition, P of {1,2,...,n} and then select a subset, S of {1,2,...,n} such that for all i in {1,2,...,n-1} if i and i+1 are in S then i and i+1 are in different blocks of P.

A227119

Number of ways to select a set partition, P of {1,2,...,n} and then select a subset, S of {1,2,...,n} such that for all i in {1,2,...,n-1} if i and i+1 are in S then i and i+1 are in different blocks of P.

Terms

    a(0) =1a(1) =2a(2) =7a(3) =31a(4) =163a(5) =985a(6) =6676a(7) =49918a(8) =406820a(9) =3580011a(10) =33764544a(11) =339222866a(12) =3612046889a(13) =40588278875a(14) =479542299692

External references