OFFSET
0,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (2,-1,0,0,0,0,0,0,0,0,0,1,-2,1).
FORMULA
G.f.: (3 - 5*x + x^2 + x^3 + x^7 + x^11 - 2*x^12 + 3*x^13) / ((1 - x)^2 * (1 - x^12)).
a(8-n) - a(n) = -1 if n == 0 (mod 12), +1 if n == 8 (mod 12), 0 otherwise.
EXAMPLE
3 + x + x^7 + 2*x^8 + 3*x^9 + 4*x^10 + 6*x^11 + 9*x^12 + 10*x^13 + ...
MATHEMATICA
LinearRecurrence[{2, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -2, 1}, {3, 1, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 9, 10}, 70] (* Harvey P. Dale, May 27 2017 *)
PROG
(PARI) {a(n) = (n%12==0) + (n-4)^2\8}
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michael Somos, Nov 25 2002
STATUS
approved