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A113438
Third row of A113435.
1
1, 4, 16, 62, 237, 901, 3418, 12956, 49096, 186029, 704861, 2670692, 10119152, 38341126, 145273353, 550436561, 2085588866, 7902239404, 29941371656, 113447051497, 429847830217, 1628681887876, 6171031956688, 23381874459566, 88593294803061, 335677616363629
OFFSET
0,2
FORMULA
a(n) = 7*a(n-1)-15*a(n-2)+11*a(n-3)-a(n-4), n>4.
a(n) = A113435(3n+2).
G.f.: (1-x)^3 / (x^4-11*x^3+15*x^2-7*x+1).
MATHEMATICA
CoefficientList[Series[(1 - x)^3/(x^4 - 11*x^3 + 15*x^2 - 7*x + 1), {x, 0, 30}], x] (* Wesley Ivan Hurt, May 28 2015 *)
PROG
(PARI) Vec(-(x-1)^3 / (x^4-11*x^3+15*x^2-7*x+1) + O(x^100)) \\ Colin Barker, May 28 2015
CROSSREFS
Cf. A113435.
Sequence in context: A081666 A250346 A085781 * A268429 A195339 A172025
KEYWORD
nonn,easy
AUTHOR
Floor van Lamoen, Nov 04 2005
EXTENSIONS
Error in recursion and strange things in formula fixed by Colin Barker, May 28 2015
STATUS
approved