A374654 a(n) = Product_{k=0..n} (L(k)+1), where L=A000032 (Lucas numbers).

3, 6, 24, 120, 960, 11520, 218880, 6566400, 315187200, 24269414400, 3009407385600, 601881477120000, 194407717109760000, 101480828331294720000, 85649819111612743680000, 116912003087351395123200000, 258141702816871880432025600000, 922082162461866356903195443200000

Offset

0,1

Links

Robert Israel, Table of n, a(n) for n = 0..97

Formula

a(n) = Product_{k=0..n} (L(k)+1), where L=A000032 (Lucas numbers).

a(n) = a(n-1)^2/a(n-2) + a(n-1)*a(n-2)/a(n-3) - a(n-1). - Robert Israel, Jan 11 2026

Maple

f:= proc(n) option remember; procname(n-1)^2/procname(n-2) + procname(n-1)*procname(n-2)/procname(n-3) - procname(n-1) end proc:
f(0):= 3: f(1):= 6: f(2):= 24:
map(f, [$0..20]); # Robert Israel, Jan 11 2026

Mathematica

w[n_] := Product[LucasL[k] + 1, {k, 0, n}]
Table[w[n], {n, 0, 20}]

Crossrefs

Cf. A000032, A000142, A003266, A070825, A082480, A135407, A374655.

Sequence in context: A109155 A338112 A294381 * A081072 A000717 A076020

Adjacent sequences: A374651 A374652 A374653 * A374655 A374656 A374657

Keyword

nonn

Author

Clark Kimberling, Jul 25 2024

Status

approved