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Numbers n where A019294(n) > n.
4

%I #5 Aug 03 2012 04:48:46

%S 3,11,29,53,58,59,67,101,109,131,149,173,202,239,461,479,659,1031,

%T 1319,1579,1847

%N Numbers n where A019294(n) > n.

%C A number n is called (m,k)-perfect if sigma^m(n) = k*n. A019294(n) gives minimal values of m for n. a(n) are the values where A019294(n) > n.

%C Corresponding values of m and k are in A111726, A111727.

%H Graeme L. Cohen and Herman J. J. te Riele, <a href="http://www.emis.de/journals/EM/expmath/volumes/5/5.html">Iterating the sum-of-divisors function</a> Experimental Mathematics, 5 (1996), p 94.

%o (Haskell)

%o a111227 n = a111227_list !! (n-1)

%o a111227_list = filter (\x -> a019294 x > x) [1..]

%o -- _Reinhard Zumkeller_, Aug 02 2012

%K hard,nonn

%O 1,1

%A Lambert Klasen (lambert.klasen(AT)gmx.net), Oct 26 2005