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A023510
Greatest exponent in prime-power factorization of prime(n) + 1.
2
1, 2, 1, 3, 2, 1, 2, 2, 3, 1, 5, 1, 1, 2, 4, 3, 2, 1, 2, 3, 1, 4, 2, 2, 2, 1, 3, 3, 1, 1, 7, 2, 1, 2, 2, 3, 1, 2, 3, 1, 2, 1, 6, 1, 2, 3, 2, 5, 2, 1, 2, 4, 2, 2, 1, 3, 3, 4, 1, 1, 2, 2, 2, 3, 1, 1, 2, 2, 2, 2, 1, 3, 4, 1, 2, 7, 1, 1, 1, 1, 2, 1, 4, 1, 3, 2, 2, 1, 1, 4, 2, 5, 3, 2, 3, 3, 1, 2, 2
OFFSET
1,2
COMMENTS
If a(n)=1 then prime(a(n)) is a term in A049097. - Zak Seidov, Jul 20 2016
FORMULA
a(n) = A051903(A008864(n)). - Michel Marcus, Jul 20 2016
EXAMPLE
For n=5, the fifth prime is 11, and the prime factorization of 11 + 1 = 12 is 2^2*3. This has exponents 2 and 1, so a(5) is the largest of these exponents, 2. - Michael B. Porter, Jul 20 2016
MATHEMATICA
Table[Max[#[[2]] & /@ FactorInteger[Prime[k] + 1]], {k, 10000}] (* Zak Seidov, Jul 19 2016 *)
PROG
(PARI) a(n) = vecmax(factor(prime(n)+1)[, 2]) \\ Michel Marcus, Jul 20 2016
CROSSREFS
KEYWORD
nonn
STATUS
approved