Number of partitions of n in which two summands (of each size) are designated.

Terms

a(0) =1a(1) =0a(2) =1a(3) =3a(4) =7a(5) =10a(6) =20a(7) =24a(8) =45a(9) =61a(10) =103a(11) =140a(12) =246a(13) =325a(14) =517a(15) =728a(16) =1086a(17) =1472a(18) =2184a(19) =2918a(20) =4197a(21) =5638a(22) =7875a(23) =10497a(24) =14625a(25) =19272a(26) =26354a(27) =34804a(28) =46992a(29) =61490