Number of order-preserving or order-reversing full contraction mappings (of an n-chain) with exactly 1 fixed point.

A221880

Number of order-preserving or order-reversing full contraction mappings (of an n-chain) with exactly 1 fixed point.

Terms

    a(0) =1a(1) =2a(2) =8a(3) =22a(4) =57a(5) =136a(6) =315a(7) =710a(8) =1577a(9) =3460a(10) =7527a(11) =16258a(12) =34917a(13) =74624a(14) =158819a(15) =336766a(16) =711777a(17) =1500028a(18) =3152991a(19) =6611834a(20) =13835357a(21) =28894072a(22) =60234843a(23) =125363062a(24) =260512857a(25) =540599156a(26) =1120345175a(27) =2318984050a(28) =4794555477a(29) =9902285680

External references