A228763 - OEIS

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A228763

a(n) = 2^L(n) - 1, where L(n) is the n-th Lucas number (A000032).

3, 1, 7, 15, 127, 2047, 262143, 536870911, 140737488355327, 75557863725914323419135, 10633823966279326983230456482242756607, 803469022129495137770981046170581301261101496891396417650687

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

LINKS

Table of n, a(n) for n=0..11.

FORMULA

a(n) = a(n-1) + a(n-2) + a(n-1) * a(n-2) for n>1, a(0)=3, a(1)=1.

MATHEMATICA

Table[2^LucasL[n] - 1, {n, 0, 15}] (* Bruno Berselli, Sep 03 2013 *)

PROG

(Magma) [2^Lucas(n)-1: n in [0..15]]; // Bruno Berselli, Sep 03 2013

(PARI) a(n)=2^(fibonacci(n-1)+fibonacci(n+1))-1 \\ Charles R Greathouse IV, Sep 03 2013