OFFSET
0,6
LINKS
Robert Israel, Table of n, a(n) for n = 0..691
FORMULA
(n+3)*(n+2)*(n+1)*a(n) + a(n+4) + a(n+5) = 0.
MAPLE
f:= gfun:-rectoproc({(n+3)*(n+2)*(n+1)*a(n)+a(n+4)+a(n+5)=0, a(0) = 1, a(1) = 0, a(2) = 0, a(3) = 0, a(4) = 0}, a(n), remember):
map(f, [$0..20]);
MATHEMATICA
RecurrenceTable[{a[n] == -a[n-1] - (n-2)*(n-3)*(n-4)*a[n-5], a[0]==1, a[1]==0, a[2]==0, a[3]==0, a[4]==0}, a, {n, 0, 30}] (* G. C. Greubel, Aug 24 2018 *)
PROG
(PARI) m=30; v=concat([0, 0, 0, 0, -6], vector(m-5)); for(n=6, m, v[n]= -v[n-1] - (n-2)*(n-3)*(n-4)*v[n-5]); concat([1], v) \\ G. C. Greubel, Aug 24 2018
(Magma) I:=[0, 0, 0, 0, -6]; [1] cat [n le 5 select I[n] else -Self(n-1) - (n-2)*(n- 3)*(n-4)*Self(n-5): n in [1..30]]; // G. C. Greubel, Aug 24 2018
CROSSREFS
KEYWORD
sign
AUTHOR
Robert Israel, Aug 21 2018
STATUS
approved