Number of ways to select a nonempty subset s from an n-set and then partition s into blocks of equal size.
A262280
Number of ways to select a nonempty subset s from an n-set and then partition s into blocks of equal size.
Terms
- a(0) =0a(1) =1a(2) =4a(3) =11a(4) =29a(5) =72a(6) =190a(7) =527a(8) =1552a(9) =5031a(10) =18087a(11) =66904a(12) =266381a(13) =1164516a(14) =5215644a(15) =23868103a(16) =117740143a(17) =609872350a(18) =3268548406a(19) =18110463455a(20) =102867877414a(21) =620476915965
External references
- oeis: A262280