A030538 (2^n+2)*(2^n+4)*(4^n+9*2^n+38)/720.

1, 2, 6, 29, 219, 2295, 29359, 418847, 6323967, 98276543, 1549615167, 24613132095, 392371455295, 6266462052671, 100171654977855, 1602013024405823, 25626342538717503, 409974560964700479, 6559217646832380223, 104944479835032512831, 1679087657704374659391

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (31,-310,1240,-1984,1024).

Formula

G.f.: -(684*x^4-777*x^3+254*x^2-29*x+1) / ((x-1) * (2*x-1) * (4*x-1) * (8*x-1) * (16*x-1)). - Colin Barker, Aug 03 2013

Mathematica

CoefficientList[Series[-(684 x^4 - 777 x^3 + 254 x^2 - 29 x + 1) / ((x - 1) (2 x - 1) (4 x - 1) (8 x-1) (16 x - 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Aug 04 2013 *)
LinearRecurrence[{31, -310, 1240, -1984, 1024}, {1, 2, 6, 29, 219}, 30] (* Harvey P. Dale, Apr 22 2020 *)

Prog

(Magma) [(2^n+2)*(2^n+4)*(4^n+9*2^n+38)/720: n in [0..20]]; // Vincenzo Librandi, Aug 04 2013

Crossrefs

Sequence in context: A187006 A321961 A088957 * A348879 A326900 A373350

Adjacent sequences: A030535 A030536 A030537 * A030539 A030540 A030541

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved