Number of multisets of nonempty sets of nonempty multisets of positive integers with total sum n.

Terms

a(0) =1a(1) =1a(2) =3a(3) =8a(4) =20a(5) =49a(6) =123a(7) =292a(8) =701a(9) =1653a(10) =3874a(11) =8977a(12) =20711a(13) =47344a(14) =107692a(15) =243382a(16) =547264a(17) =1224048a(18) =2725483a(19) =6040796a(20) =13334354a(21) =29316445a(22) =64215841a(23) =140159357a(24) =304890958a(25) =661097630a(26) =1429083295a(27) =3080159882a(28) =6620188725a(29) =14190463947