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a(n) = gcd(A046523(n+1), A046523(n)).
3

%I #12 May 21 2017 10:27:06

%S 1,2,2,2,2,2,2,4,2,2,2,2,2,6,2,2,2,2,2,6,6,2,2,4,2,2,4,2,2,2,2,2,6,6,

%T 6,2,2,6,6,2,2,2,2,12,6,2,2,4,4,6,6,2,2,6,6,6,6,2,2,2,2,6,4,2,6,2,2,6,

%U 6,2,2,2,2,6,12,6,6,2,2,16,2,2,2,6,6,6,6,2,2,6,6,6,6,6,6,2,2,12,12,2,2,2,2

%N a(n) = gcd(A046523(n+1), A046523(n)).

%H Antti Karttunen, <a href="/A083261/b083261.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI)

%o A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ This function from _Charles R Greathouse IV_, Aug 17 2011

%o A083261(n) = gcd(A046523(n),A046523(1+n)); \\ From _Antti Karttunen_, May 21 2017

%Y Cf. A046523, A071364, A083255, A083256, A083257, A083258, A083259, A083260, A286255.

%K nonn

%O 1,2

%A _Labos Elemer_, May 09 2003