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A074695 Greatest common divisor of n and floor(n^(1/2))^2.

%I A074695 #14 Nov 19 2024 17:32:40
%S A074695 1,1,1,4,1,2,1,4,9,1,1,3,1,1,3,16,1,2,1,4,1,2,1,8,25,1,1,1,1,5,1,1,1,
%T A074695 1,5,36,1,2,3,4,1,6,1,4,9,2,1,12,49,1,1,1,1,1,1,7,1,1,1,1,1,1,7,64,1,
%U A074695 2,1,4,1,2,1,8,1,2,1,4,1,2,1,16,81,1,1,3,1,1,3,1,1,9,1,1,3,1,1,3,1,1,9,100
%N A074695 Greatest common divisor of n and floor(n^(1/2))^2.
%H A074695 Reinhard Zumkeller, <a href="/A074695/b074695.txt">Table of n, a(n) for n = 1..10000</a>
%F A074695 a(n) = GCD(n, A048760(n)).
%F A074695 a(n) = n iff n is a square.
%F A074695 a(A258613(n)) = 1; a(A258614(n)) > 1. - _Reinhard Zumkeller_, Jun 05 2015
%t A074695 Table[GCD[n,Floor[Sqrt[n]]^2],{n,100}] (* _Harvey P. Dale_, Aug 12 2018 *)
%o A074695 (Haskell)
%o A074695 a074695 n = gcd n $ a048760 n  -- _Reinhard Zumkeller_, Jun 05 2015
%o A074695 (PARI) a(n) = gcd(n, sqrtint(n)^2); \\ _Amiram Eldar_, Nov 19 2024
%Y A074695 Cf. A000196, A000290, A048760.
%Y A074695 Cf. A258613, A258614.
%K A074695 nonn
%O A074695 1,4
%A A074695 _Reinhard Zumkeller_, Sep 03 2002