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A051063
27*n+9 or 27*n+18.
2
9, 18, 36, 45, 63, 72, 90, 99, 117, 126, 144, 153, 171, 180, 198, 207, 225, 234, 252, 261, 279, 288, 306, 315, 333, 342, 360, 369, 387, 396, 414, 423, 441, 450, 468, 477, 495, 504, 522, 531, 549, 558, 576, 585, 603, 612, 630, 639, 657, 666
OFFSET
1,1
REFERENCES
Letter from Gary W. Adamson concerning Prouhet-Thue-Morse sequence, Nov. 11, 1999.
FORMULA
a(n)=27*n-a(n-1) for n>0, a(0)=9. [Vincenzo Librandi, Aug 06 2010]
G.f. 9*x*( 1+x+x^2 ) / ( (1+x)*(x-1)^2 ). - R. J. Mathar, Sep 18 2013
MATHEMATICA
LinearRecurrence[{1, 1, -1}, {9, 18, 36}, 60] (* Harvey P. Dale, Mar 09 2022 *)
CROSSREFS
Equals 9*A001651(n).
Sequence in context: A191268 A109668 A234598 * A173942 A162689 A033896
KEYWORD
nonn,easy
STATUS
approved