A026543 Expansion of 1/((1-2*x)*(1-6*x)*(1-7*x)*(1-12*x)).

1, 27, 481, 7191, 98161, 1272663, 16005025, 197611623, 2412718033, 29257382583, 353312653057, 4255864465671, 51186427162417, 615069092006487, 7386770412718177, 88683539390560935, 1064502765417159313

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• G. C. Greubel, Table of n, a(n) for n = 0..915
• Index entries for linear recurrences with constant coefficients, signature (27,-248,900,-1008)

Crossrefs

Cf. A000079, A016129, A016304, A026542.

Programs

Magma

[(-2^n +225*6^n -7^(n+3) +12^(n+2))/25: n in [0..30]]; // G. C. Greubel, Apr 09 2022

Mathematica

CoefficientList[Series[1/((1-2x)(1-6x)(1-7x)(1-12x)),{x,0,30}],x] (* Harvey P. Dale, Apr 18 2019 *)

SageMath

[(-2^n +225*6^n -7^(n+3) +12^(n+2))/25 for n in (0..30)] # G. C. Greubel, Apr 09 2022

Formula

a(n) = (-2^n + 225*6^n - 7^(n+3) + 12^(n+2))/25. - R. J. Mathar, Jun 23 2013

E.g.f.: 1/25 (-exp(2*x) + 225*exp(6*x) - 343*exp(7*x) + 144*exp(12*x)). - G. C. Greubel, Apr 09 2022