Total number of parts in all plane partitions of n.

Terms

a(0) =0a(1) =1a(2) =5a(3) =14a(4) =38a(5) =85a(6) =196a(7) =401a(8) =830a(9) =1615a(10) =3119a(11) =5802a(12) =10718a(13) =19246a(14) =34276a(15) =59889a(16) =103656a(17) =176801a(18) =299025a(19) =499732a(20) =828638a(21) =1360696a(22) =2218128a(23) =3586194a(24) =5759839a(25) =9184715a(26) =14557974a(27) =22929745a(28) =35916469a(29) =55942850