A094704 Convolution of Fibonacci(n) and 10^n.

0, 1, 11, 112, 1123, 11235, 112358, 1123593, 11235951, 112359544, 1123595495, 11235955039, 112359550534, 1123595505573, 11235955056107, 112359550561680, 1123595505617787, 11235955056179467, 112359550561797254

Offset

0,3

Comments

The convolution of Fibonacci(n) and k^n for k > 1 has a(n) = (1/k^2 - k -1))*(2*k^(n+1) - k*Lucas(n) - (k+2)*Fibonacci(n)).

Links

G. C. Greubel, Table of n, a(n) for n = 0..990

Index entries for linear recurrences with constant coefficients, signature (11,-9,-10).

Formula

G.f. : x/((1-10*x)*(1-x-x^2)).

a(n) = (1/89)*( 10^(n+1) - 5*( ((1 + sqrt(5))/2)^n + ((1 - sqrt(5))/2)^n ) - (6/sqrt(5))*( ((1 + sqrt(5))/2)^n - ((1 - sqrt(5))/2)^n ) ).

a(n) = 10*a(n-1) + Fibonacci(n) for n >= 1. - Mark Dols, Aug 31 2009

a(n) = 11*a(n-1) - 9*a(n-2) - 10*a(n-3), n > 2. - Harvey P. Dale, Mar 18 2013

a(n) = (1/89)*( 10^(n+1) - Fibonacci(n+3) - 8*Fibonacci(n+1) ). - G. C. Greubel, Feb 09 2023

Mathematica

CoefficientList[Series[x/((1-x-x^2)(1-10x)), {x, 0, 20}], x] (* or *) LinearRecurrence[ {11, -9, -10}, {0, 1, 11}, 20] (* Harvey P. Dale, Mar 18 2013 *)

Prog

(Magma) [(10^(n+1) -Fibonacci(n+3) -8*Fibonacci(n+1))/89: n in [0..30]]; // G. C. Greubel, Feb 09 2023
(SageMath)
def A094704(n): return (10^(n+1) -fibonacci(n+3) -8*fibonacci(n+1))/89
[A094704(n) for n in range(31)] # G. C. Greubel, Feb 09 2023

Crossrefs

Cf. A000032, A000045, A019523.

Sequence in context: A065834 A104720 A132926 * A019523 A359143 A375101

Adjacent sequences: A094701 A094702 A094703 * A094705 A094706 A094707

Keyword

easy,nonn

Author

Paul Barry, May 21 2004

Status

approved