PartitionsQ

PartitionsQ[n] gives the number q(n) of partitions of the integer n into distinct parts.

Examples

Distinct partitions:

PartitionsQ[5]
(* 3 *)

Compare with PartitionsP:

{PartitionsP[10], PartitionsQ[10]}
(* {42, 10} *)

Please visit the official Wolfram Language Reference for more details.