0,2

a(n-1)=sum(P(14;n-1-k,k),k=0..ceiling((n-1)/2)), n>=1, with a(-1)=13. These are the SW-NE diagonals in P(14;n,k), the (14,1) 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.

Tanya Khovanova, Recursive Sequences

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

a(n)= a(n-1)+a(n-2), n>=2, a(0)=1, a(1)=14. a(-1):=13.

G.f.: (1+13*x)/(1-x-x^2).

a={}; b=1; c=14; AppendTo[a, b]; AppendTo[a, c]; Do[b=b+c; AppendTo[a, b]; c=b+c; AppendTo[a, c], {n, 1, 9, 1}]; a (* Vladimir Joseph Stephan Orlovsky, Jul 22 2008 *)

LinearRecurrence[{1, 1}, {1, 14}, 40] (* Harvey P. Dale, Jun 12 2017 *)

(Magma) a0:=1; a1:=14; [GeneralizedFibonacciNumber(a0, a1, n): n in [0..30]]; // Bruno Berselli, Feb 12 2013

a(n) = A109754(13, n+1) = A101220(13, 0, n+1).

Sequence in context: A087430 A085900 A075659 * A041398 A041919 A041400

Adjacent sequences: A022101 A022102 A022103 * A022105 A022106 A022107

nonn,easy

approved