OFFSET
1,6
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..17
MAPLE
a:= proc(n) option remember;
if n<6 then 1 else 3*a(n-1)*a(n-2)*a(n-3)*a(n-4) - a(n-5) fi;
end:
seq(a(n), n=1..15); # G. C. Greubel, Oct 07 2019
MATHEMATICA
a[n_]:= a[n]= If[n<6, 1, 3*a[n-1]*a[n-2]*a[n-3]*a[n-4] - a[n-5]]; Table[a[n], {n, 15}] (* modified by G. C. Greubel, Oct 07 2019 *)
PROG
(PARI) my(m=15, v=concat([1, 1, 1, 1, 1], vector(m-5))); for(n=6, m, v[n] = 3*v[n-1] *v[n-2]*v[n-3]*v[n-4] - v[n-5]); v \\ G. C. Greubel, Oct 07 2019
(Magma) [n lt 6 select 1 else 3*Self(n-1)*Self(n-2)*Self(n-3)*Self(n-4) - Self(n-5): n in [1..15]]; // G. C. Greubel, Oct 07 2019
(Sage)
def a(n):
if (n<6): return 1
else: return 3*a(n-1)*a(n-2)*a(n-3)*a(n-4) - a(n-5)
[a(n) for n in (1..15)] # G. C. Greubel, Oct 07 2019
(GAP)
a:= function(n)
if n<6 then return 1;
else return 3*a(n-1)*a(n-2)*a(n-3)*a(n-4) - a(n-5);
fi;
end;
List([1..15], n-> a(n) ); # G. C. Greubel, Oct 05 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Sep 09 2006
EXTENSIONS
Edited by N. J. A. Sloane, Sep 15 2006
Definition adapted to offset by Georg Fischer, Jun 18 2021
STATUS
approved