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A232547
Numbers n such that sigma(n^2) mod sigma(n) = n.
2
7581, 988893, 1658073, 468539757, 35124206517
OFFSET
1,1
COMMENTS
a(6) > 10^12. - Giovanni Resta, Jun 10 2016
CROSSREFS
Cf. A000203 (sigma(n) = sum of divisors of n), A065764, A232703, A247222.
Sequence in context: A254902 A257204 A204358 * A028539 A234204 A190077
KEYWORD
nonn,more
AUTHOR
Alex Ratushnyak, Nov 25 2013
EXTENSIONS
a(5) from Giovanni Resta, Jun 10 2016
STATUS
approved