Number of parts in all proper twice partitions of n.

Terms

a(0) =3a(1) =21a(2) =61a(3) =205a(4) =474a(5) =1246a(6) =2723a(7) =6277a(8) =12961a(9) =28682a(10) =56976a(11) =118919a(12) =234715a(13) =473988a(14) =913011a(15) =1807211a(16) =3430048a(17) =6648397a(18) =12500170a(19) =23764885a(20) =44174088a(21) =83090853a(22) =152803509a(23) =283387971a(24) =517516615a(25) =949775754a(26) =1719088271a(27) =3127641937a(28) =5618833687a(29) =10133255636