A341303 a(n) = n!-6*Catalan(n)+5*2^n+4*binomial(n,2)-2*Fibonacci(n)-14*n+20.

2, 2, 8, 228, 3086, 32998, 336238, 3533094, 39574232, 477773836, 6222604044, 87162325914, 1307616361780, 20922578067962, 355686650879752, 6402370841201732, 121645089807866376, 2432901968797147330, 51090942024922302314, 1124000727228733234894

Offset

3,1

Links

Paolo Xausa, Table of n, a(n) for n = 3..400

Michael Engen and Vincent Vatter, Containing all permutations, Amer. Math. Monthly, 128 (2021), 4-24; arXiv preprint, arXiv:1810.08252 [math.CO], 2018-2020.

Mathematica

Table[n! - 6*CatalanNumber[n] - 2*Fibonacci[n] + 5*(4 + 2^n) + 2*n*(n - 8), {n, 3, 25}] (* Paolo Xausa, Sep 30 2024 *)

Crossrefs

Cf. A000045, A000108.

Sequence in context: A069561 A180370 A326939 * A011148 A365307 A351400

Adjacent sequences: A341300 A341301 A341302 * A341304 A341305 A341306

Keyword

nonn

Author

N. J. A. Sloane, Feb 13 2021

Status

approved