A141295 - OEIS

%I #4 Mar 30 2012 18:51:00

%S 1,2,3,4,5,3,7,5,5,3,11,7,13,3,5,5,17,3,19,5,5,3,23,8,9,3,5,5,29,3,31,

%T 5,5,3,9,7,37,3,5,5,41,3,43,5,5,3,47,8,13,3,5,5,53,3,9,5,5,3,59,7,61,

%U 3,5,5,9,3,67,5,5,3,71,9,73,3,5,5,13,3,79,5,5,3,83,7,9,3,5,5,89,3,13,5,5,3

%N Largest m<=n such that all k with 1<=k<=m are divisors of n or coprime to n.

%C n mod a(n) = 0 or GCD(n,a(n)) = 1;

%C a(n) = n iff n=1 or n=4 or n is prime; a(A046022(n))=A046022(n);

%C a(p^2) = 2*p - 1 for odd primes p.

%H R. Zumkeller, <a href="/A141295/b141295.txt">Table of n, a(n) for n = 1..10000</a>

%Y Cf. A027750, A038566, A076274.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Jun 23 2008