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Smallest m > n such that gcd(m, n^2) = n.
4

%I #16 Oct 18 2019 23:36:37

%S 2,6,6,12,10,30,14,24,18,30,22,60,26,42,30,48,34,90,38,60,42,66,46,

%T 120,50,78,54,84,58,210,62,96,66,102,70,180,74,114,78,120,82,210,86,

%U 132,90,138,94,240,98,150,102,156,106,270,110,168,114,174,118,420,122

%N Smallest m > n such that gcd(m, n^2) = n.

%C Equals n multiplied by the least nontrivial number coprime to n. - _Amarnath Murthy_, Nov 20 2005

%H Ivan Neretin, <a href="/A087560/b087560.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = n*A053669(n).

%F A000005(a(n)) = 2*A000005(n) = A062011(n). - _Reinhard Zumkeller_, May 17 2006

%t Table[n*Select[Prime[Range[Log2[n] + 1]], ! Divisible[n, #] &][[1]], {n, 61}] (* _Ivan Neretin_, May 21 2015 *)

%Y Cf. A119416.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Oct 24 2003