Number of partitions of n-set with 2 block sizes.

Terms

a(0) =3a(1) =10a(2) =50a(3) =116a(4) =560a(5) =1730a(6) =6123a(7) =30122a(8) =116908a(9) =507277a(10) =2492737a(11) =15328119a(12) =56182092a(13) =441156796a(14) =2093130576a(15) =15965840718a(16) =77353276330a(17) =693400983344