A228789 - OEIS

%I #16 Sep 17 2013 13:19:13

%S 5,3,9,17,129,2049,262145,536870913,140737488355329,

%T 75557863725914323419137,10633823966279326983230456482242756609,

%U 803469022129495137770981046170581301261101496891396417650689

%N a(n) = 2^L(n) + 1, where L(n) is A000032(n).

%F a(n+2) = a(n)*a(n+1) - a(n) - a(n+1) + 2.

%F Binet type formula: log_2(a(n)-1) = r^n - s^n where r and s are the roots of x^2-x-1 = 0. (This is true the definition).

%t Table[1 + 2^LucasL[n], {n, 0, 11}] (* _T. D. Noe_, Sep 17 2013 *)

%Y Cf. A000032.

%K nonn,easy

%O 0,1

%A M. Tamba and _Yeshwant Shivrai Valaulikar_, Sep 04 2013