A284695 Greatest prime number appearing in the prime tower factorization of n (when n > 1); a(1) = 1.

1, 2, 3, 2, 5, 3, 7, 3, 3, 5, 11, 3, 13, 7, 5, 2, 17, 3, 19, 5, 7, 11, 23, 3, 5, 13, 3, 7, 29, 5, 31, 5, 11, 17, 7, 3, 37, 19, 13, 5, 41, 7, 43, 11, 5, 23, 47, 3, 7, 5, 17, 13, 53, 3, 11, 7, 19, 29, 59, 5, 61, 31, 7, 3, 13, 11, 67, 17, 23, 7, 71, 3, 73, 37, 5

Offset: 1

Author

Rémy Sigrist, Apr 01 2017

Keywords

• nonn

Comments

See A182318 for the definition of the prime tower factorization of a number.

a(n) >= A006530(n) for any n>0.

Examples

			8 = 2^3, hence a(8) = max(2, 3) = 3.
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A006530, A182318, A279513, A284694.

Formula

a(n) = A006530(A279513(n)) for any n>0.