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A053404
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Expansion of 1/((1+3x)(1-4x)).
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24
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1, 1, 13, 25, 181, 481, 2653, 8425, 40261, 141361, 624493, 2320825, 9814741, 37664641, 155441533, 607417225, 2472715621, 9761722321, 39434309773, 156574977625, 629786694901, 2508686426401, 10066126765213, 40170363882025
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OFFSET
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0,3
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COMMENTS
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Hankel transform is := 1,12,0,0,0,... - Philippe Deléham, Nov 02 2008
The compositions of n in which each natural number is colored by one of p different colors are called p-colored compositions of n. For n>=2, 13*a(n-2) equals the number of 13-colored compositions of n with all parts >=2, such that no adjacent parts have the same color. - Milan Janjic, Nov 26 2011
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REFERENCES
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A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.
F. P. Muga II, Extending the Golden Ratio and the Binet-de Moivre Formula, March 2014; Preprint on ResearchGate.
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LINKS
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Vincenzo Librandi, Table of n, a(n) for n = 0..1000
A. K. Whitford, Binet's formula generalized, Fib. Quart., 15 (1977), pp. 21, 24, 29.
Index entries for linear recurrences with constant coefficients, signature (1,12).
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FORMULA
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a(n) = ((4^(n+1))-(-3)^(n+1))/7.
a(n) = a(n-1) + 12*a(n-2), n > 1; a(0)=1, a(1)=1.
From Paul Barry, Jul 30 2004: (Start)
Convolution of 4^n and (-3)^n.
G.f.: 1/((1+3x)(1-4x)); a(n) = Sum_{k=0..n, 4^k*(-3)^(n-k)} = Sum_{k=0..n, (-3)^k*4^(n-k)}. (End)
a(n) = Sum_{k, 0<=k<=n} A109466(n,k)*(-12)^(n-k). - Philippe Deléham, Oct 26 2008
a(n) = (sum_{1<=k<=n+1, k odd} C(n+1,k)*7^(k-1))/2^n. - Vladimir Shevelev, Feb 05 2014
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MATHEMATICA
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CoefficientList[Series[1/((1 + 3 x) (1 - 4 x)), {x, 0, 40}], x] (* Vincenzo Librandi, Feb 06 2014 *)
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PROG
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(Sage) [lucas_number1(n, 1, -12) for n in xrange(1, 25)] # Zerinvary Lajos, Apr 22 2009
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CROSSREFS
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Cf. A001045, A015441.
Sequence in context: A147145 A151776 A116524 * A122003 A123827 A105796
Adjacent sequences: A053401 A053402 A053403 * A053405 A053406 A053407
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KEYWORD
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easy,nonn,changed
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AUTHOR
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Barry E. Williams, Jan 07 2000
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EXTENSIONS
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More terms from James A. Sellers, Feb 02 2000
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STATUS
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approved
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