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A136598
Expansion of g.f. (2*x^3 + 5) / ( -x^5 + x^3 + 1).
1
5, 0, 0, -3, 0, 5, 3, 0, -8, -3, 5, 11, 3, -13, -14, 2, 24, 17, -15, -38, -15, 39, 55, 0, -77, -70, 39, 132, 70, -116, -202, -31, 248, 272, -85, -450, -303, 333, 722, 218, -783, -1025, 115, 1505, 1243, -898, -2530, -1128, 2403, 3773, 230, -4933, -4901, 2173, 8706, 5131, -7106, -13607
OFFSET
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
Cf. A133394.
Sequence in context: A287703 A316480 A099224 * A193524 A300237 A105077
KEYWORD
sign,easy
AUTHOR
Michael Somos, Jan 11 2008
STATUS
approved