A147838 a(n)=8*a(n-1)-6*a(n-2), a(0)=1, a(1)=6 .

1, 6, 42, 300, 2148, 15384, 110184, 789168, 5652240, 40482912, 289949856, 2076701376, 14873911872, 106531086720, 763005222528, 5464855259904, 39140810744064, 280337354393088, 2007853970680320, 14380807639084032

Offset: 0

Author

Philippe Deléham, Nov 14 2008

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (8, -6).

Programs

Mathematica

LinearRecurrence[{8,-6},{1,6},40] (* Harvey P. Dale, Mar 01 2012 *)

Formula

a(n)=Sum_{k, 0<=k<=n}A147703(n,k)*5^k . G.f.: (1-2x)/(1-8x+6*x^2).

a(n)= ((5+sqrt(10))/10)*(4+sqrt(10))^n + ((5-sqrt(10))/10)*(4-sqrt(10))^n [From Richard Choulet, Nov 20 2008]