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A168074 Duplicate of A061891. 1
1, 1, 4, 7, 7, 10, 13, 13, 16, 19, 19, 22, 25, 25, 28, 31, 31, 34, 37, 37, 40, 43, 43, 46, 49, 49, 52, 55, 55, 58, 61, 61, 64, 67, 67, 70, 73, 73, 76, 79, 79, 82, 85, 85, 88, 91, 91, 94, 97, 97, 100, 103, 103, 106, 109, 109, 112, 115, 115, 118 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
FORMULA
G.f.: (1+3x^2+2x^3)/((1-x)^2*(1+x+x^2)).
a(n) = A168075(n)/(-3)^n.
a(n) = A061891(n). - Georg Fischer, Oct 14 2018
MATHEMATICA
LinearRecurrence[{1, 0, 1, -1}, {1, 1, 4, 7}, 50] (* G. C. Greubel, Jul 09 2016 *)
CoefficientList[Series[(1 + 3 x^2 + 2 x^3) / ((1 - x)^2 (1 + x + x^2)), {x, 0, 60}], x] (* Vincenzo Librandi, Jul 10 2016 *)
PROG
(PARI) Vec((1+3*x^2+2*x^3)/((1-x)^2*(1+x+x^2)) + O(x^70)) \\ Michel Marcus, Dec 03 2014
(Magma) I:=[1, 1, 4, 7]; [n le 4 select I[n] else Self(n-1)+Self(n-3)-Self(n-4): n in [1..70]]; // Vincenzo Librandi, Jul 10 2016
CROSSREFS
Sequence in context: A310930 A131432 A088744 * A061891 A310931 A310932
KEYWORD
dead
AUTHOR
Paul Barry, Nov 18 2009
EXTENSIONS
Corrected by R. J. Mathar, Dec 03 2014
STATUS
approved

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Last modified April 17 16:58 EDT 2024. Contains 371765 sequences. (Running on oeis4.)