OFFSET
0,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,-1,0,1).
FORMULA
a(n) = -a(n-3) + a(n-5). a(-n) = A133394(n).
EXAMPLE
5 - 3*x^3 + 5*x^5 + 3*x^6 - 8*x^8 - 3*x^9 + 5*x^10 + 11*x^11 + 3*x^12 - ...
PROG
(PARI) {a(n) = if( n<0, n = 1 - n; polsym(x^5 - x^3 - 1, n)[n], n++; polsym(x^5 + x^2 - 1, n)[n])}
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Michael Somos, Jan 11 2008
STATUS
approved