OFFSET
1,2
FORMULA
Sum_{n>=1} 1/(2^a(n)) = 1/2+1/(2^2)+1/(2^3)+1/(2^5)+1/(2^8)+... = 0.910163879394531305517927948...
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jan 27 2006
EXTENSIONS
Simplified definition - R. J. Mathar, Oct 01 2009
STATUS
approved