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A137256 Binomial transform of 2^n, 2^n, 2^n. 1
1, 2, 4, 9, 21, 48, 108, 243, 549, 1242, 2808, 6345, 14337, 32400, 73224, 165483, 373977, 845154, 1909980, 4316409, 9754749, 22044960, 49819860, 112588947, 254442141, 575019162, 1299497904, 2936762649, 6636851721, 14998760928 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Sequence is identical to half its third differences.

LINKS

Table of n, a(n) for n=0..29.

Index entries for linear recurrences with constant coefficients, signature (3, -3, 3).

FORMULA

Also a(n)=3a(n-1)-3a(n-2)+3a(n-3), A052103.

O.g.f.: -(1-x+x^2)/(-1+3*x-3*x^2+3*x^3). - R. J. Mathar, Apr 02 2008

MATHEMATICA

LinearRecurrence[{3, -3, 3}, {1, 2, 4}, 30] (* Ray Chandler, Sep 23 2015 *)

CROSSREFS

Cf. A051164.

Sequence in context: A027711 A307548 A084634 * A051164 A182904 A281425

Adjacent sequences:  A137253 A137254 A137255 * A137257 A137258 A137259

KEYWORD

nonn

AUTHOR

Paul Curtz, Mar 11 2008

EXTENSIONS

More terms from R. J. Mathar, Apr 02 2008

STATUS

approved

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Last modified September 18 07:39 EDT 2020. Contains 337166 sequences. (Running on oeis4.)