A147690 - OEIS

A147690

a(0)=1; thereafter a(n+1)=F(n+3)*a(n)+F(n+3) where F_n is Fibonacci's sequence 0,1,1,2,3,5,8, etc

1, 4, 15, 80, 648, 8437, 177198, 6024766, 331362185, 29491234554, 4246737775920, 989489901789593, 373037692974676938, 227552992714552932790, 224594803809263744664717, 358677901683394200229554646, 926823697949890613393169207848

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..16.

FORMULA

a(n) ~ c * ((1 + sqrt(5))/2)^(n*(n+5)/2) / 5^(n/2), where c = 2.8108236954842730572761317698844943576850363911506448409307848569379046... . - Vaclav Kotesovec, May 05 2015

MATHEMATICA

RecurrenceTable[{a[0]==1, a[n+1]==Fibonacci[n+3]*(a[n]+1)}, a, {n, 0, 20}] (* Vaclav Kotesovec, May 05 2015 *)

PROG

(PARI) fa(n) = if (n == 0, 1, fibonacci(n+2) * (fa(n-1) + 1)); \\ Michel Marcus, Sep 05 2013

CROSSREFS

Sequence in context: A232042 A125307 A073479 * A350830 A068313 A174661

Adjacent sequences: A147687 A147688 A147689 * A147691 A147692 A147693

KEYWORD

nonn

AUTHOR

Andrew-David Bjork (abjork(AT)math.uci.edu), Nov 10 2008

STATUS

approved