A171495 a(n) = 3*a(n-1)+4 for n > 0; a(0) = 6.

6, 22, 70, 214, 646, 1942, 5830, 17494, 52486, 157462, 472390, 1417174, 4251526, 12754582, 38263750, 114791254, 344373766, 1033121302, 3099363910, 9298091734, 27894275206, 83682825622, 251048476870, 753145430614, 2259436291846

Offset: 0

Author

Klaus Brockhaus, Dec 10 2009

Keywords

• nonn

Comments

Binomial transform of A171494; second binomial transform of A010726.

Inverse binomial transform of A171496.

Links

• Index entries for linear recurrences with constant coefficients, signature (4, -3).

Crossrefs

Equals 2*A171498.

Cf. A010726 (repeat 6, 10), A171494, A171496.

Programs

Mathematica

NestList[3#+4&,6,30] (* Harvey P. Dale, Aug 25 2019 *)

PARI

{m=25; v=concat([6], vector(m-1)); for(n=2, m, v[n]=3*v[n-1]+4); v}

Formula

a(n) = 2*(4*3^n-1).

G.f.: 2*(3-x)/((1-x)*(1-3*x)).