A215195 Numbers n such that A143615(n) = sigma(n) where sigma(n) = A000203(n).

1, 598, 1498, 54797260

Offset: 1

Author

Naohiro Nomoto, Aug 05 2012

Keywords

• nonn
• more

Comments

a(5) (if it exists) > 10^8. - Hiroaki Yamanouchi, Sep 11 2014

Crossrefs

Cf. A000203, A143615.

Programs

PARI

isok(n) = sum(m=1, n, if (gcd(n,m)==1, numdiv(m))) == sigma(n); \\ Michel Marcus, Nov 08 2014

Extensions

a(4) from Hiroaki Yamanouchi, Sep 11 2014