A051398 a(n) = -(n-3)*a(n-1) + 2*(n-2)^2.

2, 6, 6, 14, -6, 102, -514, 3726, -29646, 267014, -2669898, 29369166, -352429654, 4581585894, -64142202066, 962133031502, -15394128503454, 261700184559366, -4710603322067866, 89501463119290254, -1790029262385804198, 37590614510101889126

Offset

3,1

Links

Stefano Spezia, Table of n, a(n) for n = 3..452

Alexsandar Petojevic, The Function vM_m(s; a; z) and Some Well-Known Sequences, Journal of Integer Sequences, Vol. 5 (2002), Article 02.1.7

Formula

a(n) = A056158(n) + 2n.

Mathematica

a[3]=2; a[n_]:=a[n]=-(n-3)*a[n-1]+2*(n-2)^2; Array[a, 22, 3] (* Stefano Spezia, Sep 16 2022 *)
nxt[{n_, a_}]:={n+1, 2(n-1)^2-a(n-2)}; NestList[nxt, {3, 2}, 30][[;; , 2]] (* Harvey P. Dale, Nov 18 2024 *)

Crossrefs

Cf. A056158.

Sequence in context: A065420 A119312 A309415 * A073131 A206490 A343315

Adjacent sequences: A051395 A051396 A051397 * A051399 A051400 A051401

Keyword

sign

Author

Aleksandar Petojevic

Status

approved