A022105 Fibonacci sequence beginning 1, 15.

1, 15, 16, 31, 47, 78, 125, 203, 328, 531, 859, 1390, 2249, 3639, 5888, 9527, 15415, 24942, 40357, 65299, 105656, 170955, 276611, 447566, 724177, 1171743, 1895920, 3067663, 4963583, 8031246, 12994829

Offset

0,2

Comments

a(n-1)=sum(P(15;n-1-k,k),k=0..ceiling((n-1)/2)), n>=1, with a(-1)=14. These are the SW-NE diagonals in P(15;n,k), the (15,1) Pascal triangle. Cf. A093645 for the (10,1) Pascal triangle. Observation by Paul Barry, Apr 29 2004. Proof via recursion relations and comparison of inputs.

Links

Table of n, a(n) for n=0..30.

Tanya Khovanova, Recursive Sequences

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

Formula

a(n)= a(n-1)+a(n-2), n>=2, a(0)=1, a(1)=15. a(-1):=14.

G.f.: (1+14*x)/(1-x-x^2).

a(n) = A101220(14,0,n+1). - Ross La Haye, May 02 2006

Mathematica

a={}; b=1; c=15; AppendTo[a, b]; AppendTo[a, c]; Do[b=b+c; AppendTo[a, b]; c=b+c; AppendTo[a, c], {n, 1, 12, 1}]; a (* Vladimir Joseph Stephan Orlovsky, Jul 23 2008 *)
LinearRecurrence[{1, 1}, {1, 15}, 40] (* Harvey P. Dale, Oct 11 2015 *)

Prog

(Magma) a0:=1; a1:=15; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013

Crossrefs

a(n) = A109754(14, n+1).

a(k) = A118654(4, k).

Sequence in context: A193566 A079832 A037971 * A041456 A041458 A041454

Adjacent sequences: A022102 A022103 A022104 * A022106 A022107 A022108

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved