A083259 - OEIS

%I #13 Jan 22 2020 20:09:04

%S 1,2,1,4,1,6,1,8,1,2,1,12,1,2,3,16,1,18,1,4,3,2,1,24,1,2,1,4,1,30,1,

%T 32,3,2,1,36,1,2,3,8,1,6,1,4,3,2,1,48,1,2,3,4,1,54,1,8,3,2,1,60,1,2,3,

%U 64,1,6,1,4,3,10,1,72,1,2,3,4,1,6,1,16,1,2,1,12,1,2,3,8,1,90,1,4,3,2,1,96,1

%N a(n) = gcd(n, A071364(n)), where A071364(n) is the smallest number with same sequence of exponents in canonical prime factorization as n.

%H Antti Karttunen, <a href="/A083259/b083259.txt">Table of n, a(n) for n = 1..16384</a>

%H Antti Karttunen, <a href="/A083259/a083259.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%o (PARI)

%o A071364(n) = { my(f=factor(n)); for(i=1, #f~, f[i, 1] = prime(i)); factorback(f); }; \\ From A071364

%o A083259(n) = gcd(A071364(n),n); \\ _Antti Karttunen_, Jan 22 2020

%Y Cf. A007395, A002808, A046523, A071364, A083255-A083260, A322361, A330749.

%K nonn

%O 1,2

%A _Labos Elemer_, May 09 2003