OFFSET
1,8
COMMENTS
The n for which the count is nonzero are listed in A051204.
LINKS
R. J. Mathar, Table of n, a(n) for n = 1..136
Maohua Le, On the number of solutions of the generalized Ramanujan-Nagell equation x^2-d=2^(n+2), Acta Arithm. 60 (1991) 149.
R. J. Mathar, The number of representations of n of the form n=x^2-2^y [PDF]
Nicholas Tzanakis, On the diophantine equation y^2-d=2^k, J. Number Theory 17 (1983) 144.
CROSSREFS
KEYWORD
nonn
AUTHOR
R. J. Mathar, Oct 19 2014
STATUS
approved