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A123009 Expansion of -x * (5*x+1) / (49*x^2+2*x-1). 0
1, 7, 63, 469, 4025, 31031, 259287, 2039093, 16783249, 133482055, 1089343311, 8719307317, 70816436873, 568878932279, 4607763271335, 37090594224341, 299961588744097, 2417362294480903, 19532842437422559, 157516437304409365 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..20.

Index to sequences with linear recurrences with constant coefficients, signature (2,49).

FORMULA

a(n) = 2*a(n-1)+49*a(n-2) for n>2. G.f.: -x*(5*x+1)/(49*x^2+2*x-1). [Colin Barker, Oct 19 2012]

MATHEMATICA

M := {{0, 1}, {1, 2/7}}; v[1] = {1, 1}; v[n_] := v[n] = M.v[n - 1]; a = Table[v[n][[1]]*7^(n - 1), {n, 1, 30}]

CROSSREFS

Cf. A002534.

Sequence in context: A043027 A165759 A166153 * A219058 A182603 A218191

Adjacent sequences:  A123006 A123007 A123008 * A123010 A123011 A123012

KEYWORD

nonn,easy

AUTHOR

Roger L. Bagula and Gary W. Adamson, Sep 23 2006

EXTENSIONS

Sequence edited by Joerg Arndt and Colin Barker, Oct 19 2012.

STATUS

approved

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Last modified October 24 22:48 EDT 2014. Contains 248516 sequences.