a(n) is the number of different hooklength lists of the plane partitions of n.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =6a(5) =11a(6) =19a(7) =31a(8) =52a(9) =86a(10) =146a(11) =231a(12) =392a(13) =615a(14) =1006a(15) =1594a(16) =2612a(17) =4062a(18) =6518a(19) =10116a(20) =15958a(21) =24557a(22) =38565a(23) =58548