A234286 Positive odd numbers n such that 2m - sigma(m) is never equal to n, where sigma(.) is the sum of divisors function A000203. Conjectural.

3, 9, 13, 15, 17, 21, 23, 27, 29, 31, 33, 35, 39, 43, 45, 49

Offset: 1

Author

N. J. A. Sloane, Dec 28 2013

Keywords

• nonn
• more
• hard

Comments

The terms shown here are conjectural, based on a search up to 10^20 made by Davis et al. (2013).

Links

• Nichole Davis, Dominic Klyve and Nicole Kraght, On the difference between an integer and the sum of its proper divisors, Involve, Vol. 6 (2013), No. 4, 493-504; DOI: 10.2140/involve.2013.6.493

Crossrefs

Cf. A000203, A033879 (2n - sigma(n)).

For negative values of n see A234285.