Number of permutations of [n] with no fixed points where the maximal displacement of an element equals two.
A321048
Number of permutations of [n] with no fixed points where the maximal displacement of an element equals two.
Terms
- a(0) =0a(1) =2a(2) =3a(3) =6a(4) =12a(5) =24a(6) =44a(7) =84a(8) =159a(9) =300a(10) =564a(11) =1064a(12) =2004a(13) =3774a(14) =7107a(15) =13386a(16) =25208a(17) =47472a(18) =89400a(19) =168360a(20) =317055a(21) =597080a(22) =1124424a(23) =2117520a(24) =3987720a(25) =7509690a(26) =14142275a(27) =26632782a(28) =50154948a(29) =94451976
External references
- oeis: A321048