OFFSET
0,3
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (-4,-3).
FORMULA
Equals A038608 o A003462 = A033999 * A003462, i.e., a(n) = (-1)^n*A003462(n) = (-1)^A003462(n)*A003462(n) = A038608(A003462(n)). - M. F. Hasler, Oct 21 2014
From Colin Barker, Oct 22 2014: (Start)
a(n) = -4*a(n-1) - 3*a(n-2).
G.f.: -x / ((1+x)*(1+3*x)). (End)
E.g.f.: (-1)*exp(-2*x)*sinh(x). - G. C. Greubel, Jun 18 2021
MATHEMATICA
Table[(-1)^n*(3^n -1)/2, {n, 0, 30}] (* G. C. Greubel, Jun 18 2021 *)
PROG
(PARI) concat(0, Vec(-x/((x+1)*(3*x+1)) + O(x^100))) \\ Colin Barker, Oct 22 2014
(Sage) [(-1)^n*(3^n -1)/2 for n in (0..30)] # G. C. Greubel, Jun 18 2021
CROSSREFS
KEYWORD
sign,easy
AUTHOR
M. F. Hasler, Oct 21 2014
EXTENSIONS
Former duplicate of A003462 changed to the signed variant by M. F. Hasler, Oct 21 2014
STATUS
approved