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A191869
First differences of the dying rabbits sequence A000044.
1
0, 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 88, 143, 231, 373, 603, 974, 1574, 2543, 4109, 6639, 10727, 17332, 28004, 45248, 73109, 118126, 190862, 308385, 498273, 805084, 1300814, 2101789, 3395964, 5487026, 8865658, 14324680, 23145090, 37396661, 60423625
OFFSET
1,5
FORMULA
G.f.: x^3(1 + x + x^2 + x^3 + x^4)(1 - x + x^2 - x^3 + x^4)/(1 - x - x^3 - x^5 - x^7 - x^9 - x^11). - Charles R Greathouse IV, Jun 19 2011
MATHEMATICA
A000044 = CoefficientList[Series[1/(1 - z - z^3 - z^5 - z^7 - z^9 - z^11), {z, 0, 200}], z]; GetDiff[seq_List] := Drop[seq, 1] - Drop[seq, -1]; A191869 = GetDiff[A000044]
PROG
(PARI) A191869_list=Vec((-x^11-x^9-x^7-x^5-x^3)/(x^11+x^9+x^7+x^5+x^3+x-1)+O(x^99)) /* returns a list of the first 96 nonzero terms, a(3)...a(99) */
(PARI) A191869(n)=polcoeff((1+x^2+x^4+x^6+x^8)/(1-x-x^3-x^5-x^7-x^9-x^11+O(x^max(1, n-2))), n-3) \\ M. F. Hasler, Jun 19 2011
CROSSREFS
Cf. A000044.
Sequence in context: A023440 A225396 A290689 * A077373 A202278 A132634
KEYWORD
nonn,easy
AUTHOR
STATUS
approved