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%I #11 Mar 29 2016 06:10:37
%S 1,1,2,1,2,2,2,2,2,3,1,2,3,2,2,2,3,2,2,2,2,2,3,3,2,3,2,2,3,3,1,3,3,3,
%T 3,2,2,2,3,3,3,3,2,2,3,2,2,2,3,3,3,3,2,3,3,3,3,2,2,3,2,3,3,3,2,3,2,2,
%U 3,3,3,3,2,3,3,2,4,2,3,3,4,2,2,3,3,3,3,2,4,2,3,3,2,3,2
%N Number of primes dividing p+1 as p runs through the primes.
%H T. D. Noe, <a href="/A008335/b008335.txt">Table of n, a(n) for n=1..10000</a>
%F a(n) = A001221(A008864(n)). - _Michel Marcus_, Mar 29 2016
%p for i from 1 to 500 do if isprime(i) then print(nops(factorset(i+1))); fi; od;
%o (PARI) a(n) = omega(prime(n)+1); \\ _Michel Marcus_, Mar 29 2016
%Y Cf. A001221, A008864.
%K nonn
%O 1,3
%A _N. J. A. Sloane_.
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