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.

Showing 1-2 of 2 results.

A218404 Numbers k for which sigma(k)/k - 1/4 is an integer.

Original entry on oeis.org

40, 224, 360, 2016, 174592, 524160, 1571328, 492101632, 4428914688, 83350779494400, 2163091537152000, 2251247910912000, 2931032952207360, 7487050986455040, 155086041146982400, 369127262068899840, 12682035945406464000, 12848564519239680000
Offset: 1

Views

Author

Zdenek Cervenka, Oct 28 2012

Keywords

Comments

a(10) > 10^11. - Donovan Johnson, Oct 31 2012
a(10) > 10^12. - Giovanni Resta, Nov 04 2012
Note that there are no terms here with abundancy 5/4. - Michel Marcus, Jun 26 2013

Crossrefs

Cf. A159907, A218405.

Extensions

a(8)-a(9) from Donovan Johnson, Oct 31 2012
a(10)-a(18) from Michel Marcus, Jun 26 2013

A218429 Numbers k for which sigma(k)/k - 7/8 is an integer.

Original entry on oeis.org

8, 760320, 1468800, 4612608, 1414886400, 4935598080, 83655936000, 172888934400, 173172916224000, 225464073246720, 575926998958080, 650264059920384, 73439222840111923200, 88160928190086850560, 450645911113324953600, 600860926790121553920
Offset: 1

Views

Author

Zdenek Cervenka, Oct 28 2012

Keywords

Comments

a(8) > 10^11. - Donovan Johnson, Nov 01 2012
a(9) > 10^12. - Giovanni Resta, Nov 04 2012
Note that there are no terms here with abundancy 23/8 (k=2). - Michel Marcus, Jun 26 2013

Crossrefs

Cf. A218404, A159907, A218405.

Extensions

a(5)-a(7) from Donovan Johnson, Nov 01 2012
a(8) from Giovanni Resta, Nov 04 2012
More terms from Michel Marcus, Jun 26 2013
Showing 1-2 of 2 results.

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