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.

A218430 Numbers k for which sigma(k)/k - 2/9 is an integer.

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%I A218430 #21 May 13 2023 20:00:24
%S A218430 54,2744280,6191640,182494620,653425920,702989280,27025270272,
%T A218430 72475361280,76172903718912,15224461545984768,1688635722988634112,
%U A218430 5953066676035614584064,1608903162935227680030720,14600472124349965895417376,2263986000385276007625523200
%N A218430 Numbers k for which sigma(k)/k - 2/9 is an integer.
%C A218430 a(9) > 10^11. - _Donovan Johnson_, Nov 01 2012
%C A218430 a(9) > 10^12. - _Giovanni Resta_, Nov 04 2012
%C A218430 Note that there are no terms here with abundancy 11/9 (k=1) or 29/9 (k=3). - _Michel Marcus_, Jun 25 2013
%Y A218430 Cf. A218414, A160320, A218415, A218416, A160321, A218417, A218418.
%K A218430 nonn
%O A218430 1,1
%A A218430 _Zdenek Cervenka_, Oct 28 2012
%E A218430 a(4)-a(8) from _Donovan Johnson_, Nov 01 2012
%E A218430 More terms from _Michel Marcus_, Jun 25 2013