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%I #13 Nov 22 2014 12:42:31
%S 1,2,2,3,2,4,3,3,4,2,3,3,2,4,4,3,3,4,4,2,4,4,3,5,4,3,5,5,3,5,3,4,2,4,
%T 3,5,4,4,6,4,3,3,3,4,3,4,5,4,4,3,3,3,4,4,5,4,4,3,5,2,3,5,3,4,6,3,4,3,
%U 3,4,3,5,8,3,4,6,8,3,6
%N Sum of exponents in prime-power factorization of p(n)*p(n-1) - 1.
%H Harvey P. Dale, <a href="/A023522/b023522.txt">Table of n, a(n) for n = 2..1000</a>
%F a(n) = A001222(A023515(n)). - _Michel Marcus_, Sep 30 2013
%t PrimeOmega[Times@@#-1]&/@Partition[Prime[Range[80]],2,1] (* _Harvey P. Dale_, Nov 22 2014 *)
%o (PARI) a(n) = bigomega(prime(n)*prime(n-1) - 1); \\ _Michel Marcus_, Sep 30 2013
%K nonn
%O 2,2
%A _Clark Kimberling_
%E Offset set to 2 and a(1) removed by _Michel Marcus_, Sep 30 2013