login
A027982
Sum{(k+1)*T(n,2n-k)}, 0<=k<=2n, T given by A027960.
1
1, 10, 38, 108, 270, 632, 1426, 3148, 6854, 14784, 31674, 67508, 143278, 303016, 638882, 1343388, 2817942, 5898128, 12320650, 25689988, 53477246, 111148920, 230686578, 478150508, 989855590, 2046820192, 4227858266, 8724152148, 17985175374, 37044092744
OFFSET
0,2
FORMULA
From Colin Barker, Nov 25 2014: (Start)
a(n) = (-10+11*2^n+2*(-3+2^n)*n).
a(n) = 6*a(n-1)-13*a(n-2)+12*a(n-3)-4*a(n-4).
G.f.: -(2*x^3+9*x^2-4*x-1) / ((x-1)^2*(2*x-1)^2).
(End)
MATHEMATICA
LinearRecurrence[{6, -13, 12, -4}, {1, 10, 38, 108}, 40] (* Harvey P. Dale, Oct 28 2020 *)
PROG
(PARI) Vec(-(2*x^3+9*x^2-4*x-1)/((x-1)^2*(2*x-1)^2) + O(x^100)) \\ Colin Barker, Nov 25 2014
CROSSREFS
Sequence in context: A257051 A250420 A136840 * A064603 A164298 A050479
KEYWORD
nonn,easy
EXTENSIONS
More terms from Colin Barker, Nov 25 2014
STATUS
approved