A202277 Numbers m such that number of integers k such sigma(k) <= m (A074753) is equal to number of integers k <= m such that sigma(x) = k has no solution (A202276).

2, 537, 639, 647, 653, 655, 657, 661, 663, 672, 674, 684, 686

Offset: 1

Author

Jaroslav Krizek, Dec 25 2011

Keywords

• nonn

Comments

Numbers m such that A074753(m) - A202276(m) = 0.

Numbers m such that A202275(m) = 0 (see graph of A202275).

Conjecture: sequence is finite with 13 terms.

Crossrefs

Cf. A074753, A202275, A202276, A175523, A007369, A007368, A007609.