Number of rectangular plane partitions of n.

Terms

a(0) =1a(1) =1a(2) =3a(3) =5a(4) =10a(5) =14a(6) =26a(7) =35a(8) =58a(9) =81a(10) =124a(11) =169a(12) =257a(13) =345a(14) =501a(15) =684a(16) =968a(17) =1304a(18) =1830a(19) =2452a(20) =3387a(21) =4541a(22) =6188a(23) =8257a(24) =11193a(25) =14865a(26) =19968a(27) =26481a(28) =35341a(29) =46674