A102298 - OEIS

%I #8 Jun 09 2016 09:25:24

%S 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,

%T 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,

%U 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

%N Number of prime divisors with multiplicity of n+1 where n and n+1 are composite or twin composite numbers.

%H Harvey P. Dale, <a href="/A102298/b102298.txt">Table of n, a(n) for n = 1..1000</a>

%e For n=8 n+1 = 9 = 3*3 or 2 prime divisors with multiplicity.

%t PrimeOmega[#[[2]]]&/@Select[Partition[Range[300],2,1],And@@ CompositeQ[ #]&] (* _Harvey P. Dale_, Jun 09 2016 *)

%o (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) }

%K easy,nonn

%O 1,1

%A _Cino Hilliard_, Feb 19 2005