A199421 (5*7^n+1)/2.

3, 18, 123, 858, 6003, 42018, 294123, 2058858, 14412003, 100884018, 706188123, 4943316858, 34603218003, 242222526018, 1695557682123, 11868903774858, 83082326424003, 581576284968018, 4071033994776123, 28497237963432858

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (8,-7).

Formula

a(n) = 7*a(n-1)-3.

a(n) = 8*a(n-1)-7*a(n-2).

G.f.: 3*(1-2*x)/((1-x)*(1-7*x)).

Prog

(Magma) [(5*7^n+1)/2: n in [0..30]];

Crossrefs

Sequence in context: A074564 A108241 A342710 * A305869 A371483 A181998

Adjacent sequences: A199418 A199419 A199420 * A199422 A199423 A199424

Keyword

nonn,easy

Author

Vincenzo Librandi, Nov 07 2011

Status

approved