Number of free pure symmetric multifunctions (with empty expressions allowed) with one atom and n positions.

A277996

Number of free pure symmetric multifunctions (with empty expressions allowed) with one atom and n positions.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =5a(4) =13a(5) =36a(6) =102a(7) =299a(8) =892a(9) =2713a(10) =8364a(11) =26108a(12) =82310a(13) =261804a(14) =838961a(15) =2706336a(16) =8780725a(17) =28636157a(18) =93818641a(19) =308641277a(20) =1019140129a(21) =3376604826a(22) =11221805968a(23) =37399728251a(24) =124967677989a(25) =418564867751

External references