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%I #17 Sep 18 2015 08:19:17
%S 1,1,1,1,1,2,1,1,1,1,1,2,1,1,1,1,1,2,1,2,1,1,1,2,1,1,1,2,1,2,1,1,1,1,
%T 1,2,1,1,1,2,1,2,1,1,1,1,1,2,1,1,1,1,1,2,1,2,1,1,1,2,1,1,1,1,1,2,1,1,
%U 1,2,1,2,1,1,1,1,1,2,1,2,1,1,1,2,1,1,1,2,1,2,1,1,1,1,1,2,1,1,1,2,1,2,1,2,1
%N a(n) = floor(sigma(n)/n).
%C The sequence is unbounded. - Vrabec
%C First occurrence of k: 1,6,120,27720,..., which is A023199. - _Robert G. Wilson v_, Jun 28 2005
%C a(n) > 1 if n is perfect or abundant. a(n) = 2 if n is perfect or primitive abundant (see A091191). - _Alonso del Arte_, Feb 06 2012
%D W. Sierpinski, Elementary Theory of Numbers, 1987, p. 174 ff.
%H Reinhard Zumkeller, <a href="/A108775/b108775.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = floor(A017665(n)/A017666(n)). - _Michel Marcus_, Sep 18 2015
%e a(6) = 2 because sigma(6)/6 = (1 + 2 + 3 + 6)/6 = 2.
%t Table[ Floor[ DivisorSigma[1, n]/n], {n, 105}] (* _Robert G. Wilson v_, Jun 28 2005 *)
%o (Haskell)
%o a108775 n = div (a000203 n) n -- _Reinhard Zumkeller_, Mar 23 2013
%o (PARI) a(n) = sigma(n)\n; \\ _Michel Marcus_, Sep 18 2015
%Y Cf. A000203, A054024.
%Y Cf. A017665, A017666.
%K nonn
%O 1,6
%A _Franz Vrabec_, Jun 27 2005
%E More terms from _Robert G. Wilson v_, Jun 28 2005
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