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%I #34 Nov 07 2017 03:40:39
%S 1,1,1,1,1,2,1,1,1,10,1,6,1,2,5,1,1,1,1,2,1,2,1,2,1,2,1,14,1,10,1,1,1,
%T 2,5,3,1,2,1,10,1,2,1,2,1,2,1,2,1,5,1,2,1,2,1,2,1,2,1,60,1,2,7,1,65,2,
%U 1,2,1,10,1,1,1,2,15,2,1,2,1,2,1,2,1,84,5,2,1,2,1,10,1,2,1,2,1,6
%N a(n) = gcd(n, A001157(n)).
%H Antti Karttunen, <a href="/A179930/b179930.txt">Table of n, a(n) for n = 1..16384</a>
%F A006530(a(n)) = A082063(n). - _Reinhard Zumkeller_, Jul 10 2011
%F A020639(a(n)) = A082069(n). - _Antti Karttunen_, Nov 03 2017
%p A179930 := proc(n) igcd( n, numtheory[sigma][2](n)) ; end proc:
%p seq(A179930(n),n=1..100) ;
%t Array[GCD[#, DivisorSigma[2, #]] &, 96] (* _Michael De Vlieger_, Nov 03 2017 *)
%o (PARI) A179930(n) = gcd(n,sigma(n,2)); \\ _Antti Karttunen_, Nov 03 2017
%Y Cf. A001157, A082063, A082069, A179931, A009194.
%K nonn
%O 1,6
%A _N. J. A. Sloane_, Jul 09 2011, following a suggestion from _R. J. Mathar_