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A048481
a(n) = T(0,n) + T(1,n-1) + ... + T(n,0), array T given by A048472.
3
1, 3, 9, 27, 77, 207, 529, 1299, 3093, 7191, 16409, 36891, 81949, 180255, 393249, 852003, 1835045, 3932199, 8388649, 17825835, 37748781, 79691823, 167772209, 352321587, 738197557, 1543503927, 3221225529, 6710886459, 13958643773, 28991029311, 60129542209
OFFSET
0,2
FORMULA
Row sums of triangle A134397. Also, binomial transform of A048166. - Gary W. Adamson, Oct 23 2007
a(n) = 6*a(n-1)-13*a(n-2)+12*a(n-3)-4*a(n-4). - Colin Barker, Dec 04 2014
G.f.: (4*x^2-3*x+1) / ((x-1)^2*(2*x-1)^2). - Colin Barker, Dec 04 2014
a(n) = 2^(n+1)*(n-2) + 2*n + 5. - Christian Krause, Oct 31 2023
MATHEMATICA
LinearRecurrence[{6, -13, 12, -4}, {1, 3, 9, 27}, 40] (* Harvey P. Dale, Aug 13 2015 *)
PROG
(PARI) Vec((4*x^2-3*x+1)/((x-1)^2*(2*x-1)^2) + O(x^100)) \\ Colin Barker, Dec 04 2014
CROSSREFS
Partial sums of A048495.
Sequence in context: A135415 A182897 A228734 * A269488 A027027 A361845
KEYWORD
nonn,easy
EXTENSIONS
Corrected by T. D. Noe, Nov 08 2006
STATUS
approved