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A179930
a(n) = gcd(n, A001157(n)).
4
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, 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, 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
OFFSET
1,6
LINKS
FORMULA
A006530(a(n)) = A082063(n). - Reinhard Zumkeller, Jul 10 2011
A020639(a(n)) = A082069(n). - Antti Karttunen, Nov 03 2017
MAPLE
A179930 := proc(n) igcd( n, numtheory[sigma][2](n)) ; end proc:
seq(A179930(n), n=1..100) ;
MATHEMATICA
Array[GCD[#, DivisorSigma[2, #]] &, 96] (* Michael De Vlieger, Nov 03 2017 *)
PROG
(PARI) A179930(n) = gcd(n, sigma(n, 2)); \\ Antti Karttunen, Nov 03 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 09 2011, following a suggestion from R. J. Mathar
STATUS
approved