Number of partitions of the set {1,2,...n} having no blocks that contain both odd and even entries.

A124419

Number of partitions of the set {1,2,...n} having no blocks that contain both odd and even entries.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =10a(6) =25a(7) =75a(8) =225a(9) =780a(10) =2704a(11) =10556a(12) =41209a(13) =178031a(14) =769129a(15) =3630780a(16) =17139600a(17) =87548580a(18) =447195609a(19) =2452523325a(20) =13450200625a(21) =78697155750a(22) =460457244900

External references