Number of set partitions of [n] such that j is member of block b only if b = 1 or at least one of j-1, ..., j-9 is member of a block >= b-1.

A287672

Number of set partitions of [n] such that j is member of block b only if b = 1 or at least one of j-1, ..., j-9 is member of a block >= b-1.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =5a(4) =15a(5) =52a(6) =203a(7) =877a(8) =4140a(9) =21147a(10) =115975a(11) =678570a(12) =4213596a(13) =27643917a(14) =190873448a(15) =1382311874a(16) =10468191626a(17) =82676728870a(18) =679376431959

External references