A215195 - OEIS

A215195

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

1, 598, 1498, 54797260

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OFFSET

1,2

COMMENTS

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

LINKS

PROG

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

CROSSREFS

KEYWORD

nonn,more

AUTHOR

EXTENSIONS

a(4) from Hiroaki Yamanouchi, Sep 11 2014

STATUS

approved