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A102298
Number of prime divisors with multiplicity of n+1 where n and n+1 are composite or twin composite numbers.
1
2, 2, 2, 4, 2, 2, 2, 2, 3, 3, 2, 2, 2, 4, 2, 4, 3, 2, 2, 3, 2, 3, 2, 4, 2, 2, 3, 6, 2, 3, 2, 3, 3, 3, 2, 3, 4, 2, 2, 2, 2, 4, 2, 3, 2, 2, 2, 6, 3, 4, 3, 2, 2, 5, 2, 3, 3, 2, 2, 5, 2, 2, 2, 3, 3, 4, 2, 3, 2, 2, 4, 4, 2, 2, 2, 6, 2, 2, 3, 3, 3, 3, 2, 4, 2, 6, 2, 5, 3, 2, 2, 3, 3, 3, 3, 5, 2, 2, 2, 4, 2, 3, 2, 3, 4
OFFSET
1,1
LINKS
EXAMPLE
For n=8 n+1 = 9 = 3*3 or 2 prime divisors with multiplicity.
MATHEMATICA
PrimeOmega[#[[2]]]&/@Select[Partition[Range[300], 2, 1], And@@ CompositeQ[ #]&] (* Harvey P. Dale, Jun 09 2016 *)
PROG
(PARI) f(n) = for(x=1, n, y=composite(x)+1; if(!isprime(y), print1(bigomega(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
Sequence in context: A111735 A211454 A242310 * A049298 A075016 A279409
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Feb 19 2005
STATUS
approved