cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A111227 Numbers n where A019294(n) > n.

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%I A111227 #5 Aug 03 2012 04:48:46
%S A111227 3,11,29,53,58,59,67,101,109,131,149,173,202,239,461,479,659,1031,
%T A111227 1319,1579,1847
%N A111227 Numbers n where A019294(n) > n.
%C A111227 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 A111227 Corresponding values of m and k are in A111726, A111727.
%H A111227 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 A111227 (Haskell)
%o A111227 a111227 n = a111227_list !! (n-1)
%o A111227 a111227_list = filter (\x -> a019294 x > x) [1..]
%o A111227 -- _Reinhard Zumkeller_, Aug 02 2012
%K A111227 hard,nonn
%O A111227 1,1
%A A111227 Lambert Klasen (lambert.klasen(AT)gmx.net), Oct 26 2005