OFFSET
1,2
EXAMPLE
a(1)=1 because nonprime(1)-1=0=nonnegative nonprime and nonprime(1)+1=2=prime.
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Apr 12 2010
EXTENSIONS
Corrected (101 removed) by R. J. Mathar, Apr 16 2010
STATUS
approved