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A120849
5n+3^n-2^n.
1
0, 6, 15, 34, 85, 236, 695, 2094, 6345, 19216, 58075, 175154, 527405, 1586196, 4766655, 14316214, 42981265, 129009176, 387158435, 1161737274, 3485735925, 10458256156, 31376865415, 94134790334, 282412759385, 847255055136
OFFSET
0,2
FORMULA
G.f.: x*(6-27*x+31*x^2)/((1-2*x)*(1-3*x)*(1-x)^2). - Vincenzo Librandi, Feb 24 2013
a(n) = 7*a(n-1)-17*a(n-2)+17*a(n-3)-6*a(n-4). - Vincenzo Librandi, Feb 24 2013
MATHEMATICA
CoefficientList[Series[x (6 - 27 x + 31 x^2)/((1-2 x) (1-3 x) (1 - x)^2), {x, 0, 30}], x] (* Vincenzo Librandi, Feb 24 2013 *)
PROG
(Magma) [5*n+3^n-2^n: n in [0..30]] /* or */ I:=[0, 6, 15, 34]; [n le 4 select I[n] else 7*Self(n-1)-17*Self(n-2)+17*Self(n-3)-6*Self(n-4): n in [1..30]]; // Vincenzo Librandi, Feb 24 2013
CROSSREFS
Sequence in context: A350596 A232604 A332735 * A358210 A338053 A030661
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Aug 18 2006
EXTENSIONS
Edited by Ray Chandler, Sep 06 2006
STATUS
approved