OFFSET
1,3
EXAMPLE
For n=8 n+1=9 a twin composite pair. 8=2^3 has 1 distinct divisor, 2.
PROG
(PARI) f2(n) = for(x=1, n, y=composite(x); if(!isprime(y+1), print1(omega(y)", "))) composite(n) =\The n-th composite number. 1 is def as not prime nor composite. { local(c, x); c=1; x=1; while(c <= n, x++; if(!isprime(x), c++); ); return(x) }
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Feb 19 2005
STATUS
approved