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%I #26 Feb 22 2023 01:50:58
%S 6,2,4,6,6,4,2,6,6,2,4,6,2,2,6,2,4,4,2,6,4,2,2,4,4,2,6,6,6,6,2,4,6,6,
%T 4,2,6,6,2,4,6,6,4,2,2,4,4,2,6,4,2,2,4,6,6,6,6,6,2,4,6,2,4,4,2,6,6,6,
%U 4,2,2,4,6,2,4,6,6,4,2,6,2,2,2,6,4,2,2
%N a(n) = gcd(abundant(n), abundant(n+1)) where abundant(n) is the n-th abundant number.
%C The first occurrence of 1, 2, 3, 4, 5 and 6 is at n = 1432, 2, 231, 3, 1335014838 and 1, respectively. There are no terms larger than 6. - _Amiram Eldar_, Feb 22 2023
%H Amiram Eldar, <a href="/A061496/b061496.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Harry J. Smith)
%F a(n) = gcd(A005101(n), A005101(n+1)).
%e a(1) = gcd(12, 18) = 6.
%t GCD @@@ Partition[Select[Range[400], DivisorSigma[-1, #] > 2 &], 2, 1] (* _Amiram Eldar_, Feb 22 2023 *)
%o (PARI) { x=12; for (n=1, 1000, y=x+1; until (sigma(y) > 2*y, y++); write("b061496.txt", n, " ", gcd(x, y)); x=y ) } \\ _Harry J. Smith_, Jul 23 2009
%Y Cf. A005101.
%K nonn
%O 1,1
%A _Jason Earls_, Jun 12 2001
%E Corrected and extended by _Jason G. Wurtzel_, Nov 21 2006
%E More terms from _Sean A. Irvine_, Feb 18 2023
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