a is the limit of A321396.

Terms

a(0) =0a(1) =1a(2) =0a(3) =1a(4) =1a(5) =3a(6) =3a(7) =10a(8) =10a(9) =32a(10) =37a(11) =105a(12) =131a(13) =364a(14) =464a(15) =1269a(16) =1690a(17) =4478a(18) =6163a(19) =16070a(20) =22582a(21) =58197a(22) =83431a(23) =212337a(24) =309890a(25) =780706a(26) =1155906a(27) =2888189a(28) =4331109a(29) =10739640