A023504 - OEIS

A023504

Maximum exponent in the prime factorization of prime(n) - 1.

0, 1, 2, 1, 1, 2, 4, 2, 1, 2, 1, 2, 3, 1, 1, 2, 1, 2, 1, 1, 3, 1, 1, 3, 5, 2, 1, 1, 3, 4, 2, 1, 3, 1, 2, 2, 2, 4, 1, 2, 1, 2, 1, 6, 2, 2, 1, 1, 1, 2, 3, 1, 4, 3, 8, 1, 2, 3, 2, 3, 1, 2, 2, 1, 3, 2, 1, 4, 1, 2, 5, 1, 1, 2, 3, 1, 2, 2, 4, 3, 1, 2, 1, 4, 1, 1, 6, 3, 2, 1, 1, 1, 5, 2, 1, 1, 2, 3, 2

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A051903(A006093(n)) . - R. J. Mathar, Feb 06 2019

EXAMPLE

The seventh prime is 17, and 16 = 2^4, so a(7) = 4.

The eighth prime is 19, and 18 = 2^1 * 3^2, and since 2 is the greater exponent, a(8) = 2.

MATHEMATICA

Join[{0}, Max[FactorInteger[#][[All, 2]]]&/@(Prime[Range[2, 120]] - 1)] (* Harvey P. Dale, Aug 29 2017 *)