Number of partitions of n into at least two distinct parts.

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =1a(5) =2a(6) =3a(7) =4a(8) =5a(9) =7a(10) =9a(11) =11a(12) =14a(13) =17a(14) =21a(15) =26a(16) =31a(17) =37a(18) =45a(19) =53a(20) =63a(21) =75a(22) =88a(23) =103a(24) =121a(25) =141a(26) =164a(27) =191a(28) =221a(29) =255