A192778 - OEIS

A192778

Coefficient of x in the reduction of the n-th Fibonacci polynomial by x^3->x^2+3x+1.

0, 1, 0, 5, 4, 28, 48, 183, 424, 1315, 3420, 9864, 26756, 75237, 207128, 577345, 1597624, 4439764, 12307388, 34166643, 94769936, 262998791, 729644824, 2024614928, 5617339496, 15586328073, 43245649904, 119991232893, 332929027020

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OFFSET

1,4

COMMENTS

For discussions of polynomial reduction, see A192232 and A192744.

LINKS

Table of n, a(n) for n=1..29.

Index entries for linear recurrences with constant coefficients, signature (1,6,-1,-6,1,1).

FORMULA

a(n)=a(n-1)+6*a(n-2)-a(n-3)-6*a(n-4)+a(n-5)+a(n-6).

G.f.: x^2*(x^2+x-1)/((x^2-x-1)*(x^4+2*x^3-3*x^2-2*x+1)). [Colin Barker, Nov 23 2012]

EXAMPLE

The first five polynomials p(n,x) and their reductions:

F1(x)=1 -> 1

F2(x)=x -> x

F3(x)=x^2+1 -> x^2+1

F4(x)=x^3+2x -> x^2+5x+1

F5(x)=x^4+3x^2+1 -> 7x^2+4x+2, so that

A192777=(1,0,1,1,2,...), A192778=(0,1,0,5,4,...), A192779=(0,0,1,1,7,...)

CROSSREFS

Cf. A192744, A192232, A192616, A192772, A192777, A192779.

Sequence in context: A275960 A024067 A361983 * A051138 A157101 A237648

Adjacent sequences: A192775 A192776 A192777 * A192779 A192780 A192781

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Jul 09 2011

STATUS

approved