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 A008335 Number of primes dividing p+1 as p runs through the primes. 3
 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, 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, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS T. D. Noe, Table of n, a(n) for n=1..10000 FORMULA a(n) = A001221(A008864(n)). - Michel Marcus, Mar 29 2016 MAPLE for i from 1 to 500 do if isprime(i) then print(nops(factorset(i+1))); fi; od; PROG (PARI) a(n) = omega(prime(n)+1); \\ Michel Marcus, Mar 29 2016 CROSSREFS Cf. A001221, A008864. Sequence in context: A068212 A064131 A105194 * A106031 A055175 A025819 Adjacent sequences:  A008332 A008333 A008334 * A008336 A008337 A008338 KEYWORD nonn AUTHOR STATUS approved

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