Number of series-reduced planted compound windmills with n leaves.

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =12a(5) =36a(6) =104a(7) =331a(8) =1062a(9) =3519a(10) =11809a(11) =40327a(12) =139066a(13) =484698a(14) =1702819a(15) =6026452a(16) =21460248a(17) =76846950a(18) =276524978a(19) =999423375a(20) =3626370269a(21) =13205135288a(22) =48241233346a(23) =176757275833a(24) =649399348322