OFFSET
0,1
COMMENTS
Since the formula can be factored, there are no primes in the sequence.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).
FORMULA
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) + 384 for n > 3; a(0)=21, a(1)=285, a(2)=1365, a(3)=4221.
G.f.: 3*(95 + 460*x - 590*x^2 + 124*x^3 + 39*x^4)/(1-x)^5.
a(n) = (2*n+1)*(2*n+15)*(4*n^2+32*n+19).
a(n) = a(-n-8). - Bruno Berselli, Sep 05 2011
MATHEMATICA
Table[16n^4+256n^3+1160n^2+1088n+285, {n, 0, 30}] (* or *) LinearRecurrence[ {5, -10, 10, -5, 1}, {285, 2805, 9405, 22197, 43677}, 30] (* Harvey P. Dale, Jan 10 2017 *)
PROG
(Magma) [ 16*n^4+256*n^3+1160*n^2+1088*n+285: n in [0..27] ];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Klaus Brockhaus, Apr 24 2010
STATUS
approved