OFFSET
1,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (3, -2, -1, 1).
FORMULA
a(n)=L(6)*(F(n+1)-1)+L(5)*F(n)-L(4)*n, F(n): Fibonacci (A000045), G.F. x*(4+3*x)/((1-x-x^2)*(1-x)^2)
a(0)=4, a(1)=15, a(2)=37, a(3)=77, a(n)=3*a(n-1)-2*a(n-2)-a(n-3)+a(n-4) [From Harvey P. Dale, May 23 2011]
MATHEMATICA
LinearRecurrence[{3, -2, -1, 1}, {4, 15, 37, 77}, 40] (* or *) Rest[ CoefficientList[ Series[x (4+3x)/((1-x-x^2)(1-x)^2), {x, 0, 40}], x]](* Harvey P. Dale, May 23 2011 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
STATUS
approved