1,2

Let p be the largest prime factor of n; if p = prime(k) then set a(n) = k + 1. a(n) = A061395(n) + 1.

Table of n, a(n) for n=1..93.

a(n) = A049084(A006530(n)) + 1. A008578(a(n)) = A006530(n);

For n=30, the largest element of the set {1,2,3,5} (1 and prime divisors of 30) is 5, and 5 is a(n)=4th term of A008578, the extended set of primes.

Cf.: A061395, A049084, A006530, A008578.

Sequence in context: A241054 A257907 A139094 * A141285 A286531 A317765

Adjacent sequences: A159078 A159079 A159080 * A159082 A159083 A159084

nonn,easy

Jaroslav Krizek, Apr 05 2009

Edited by R. J. Mathar, Apr 06 2009

Correction for change of offset in A158611 and A008578 in Aug 2009 Jaroslav Krizek, Jan 27 2010

approved