INVERT transform of planar partitions.

Terms

a(0) =1a(1) =1a(2) =4a(3) =13a(4) =44a(5) =144a(6) =478a(7) =1573a(8) =5193a(9) =17118a(10) =56457a(11) =186153a(12) =613865a(13) =2024192a(14) =6674843a(15) =22010313a(16) =72579382a(17) =239331323a(18) =789198395a(19) =2602391853a(20) =8581422014a(21) =28297352194a(22) =93310894654a(23) =307693910316