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A228789
a(n) = 2^L(n) + 1, where L(n) is A000032(n).
0
5, 3, 9, 17, 129, 2049, 262145, 536870913, 140737488355329, 75557863725914323419137, 10633823966279326983230456482242756609, 803469022129495137770981046170581301261101496891396417650689
OFFSET
0,1
FORMULA
a(n+2) = a(n)*a(n+1) - a(n) - a(n+1) + 2.
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).
MATHEMATICA
Table[1 + 2^LucasL[n], {n, 0, 11}] (* T. D. Noe, Sep 17 2013 *)
CROSSREFS
Cf. A000032.
Sequence in context: A082454 A377226 A108245 * A221715 A248660 A141620
KEYWORD
nonn,easy
AUTHOR
M. Tamba and Yeshwant Shivrai Valaulikar, Sep 04 2013
STATUS
approved