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A270860 Least Quasi-Carmichael number with n prime factors. 0
35, 165, 6545, 179998, 7509579, 850253030 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..7.

EXAMPLE

6545 = 5*7*11*17 and 12, 14, 18, 24 all divide 6552.

PROG

(Perl) use ntheory ":all"; my $f=2; forcomposites { say $f++, " $_" if scalar(factor($_))==$f && is_quasi_carmichael($_); } 1e9; # Dana Jacobsen, Apr 27 2017

CROSSREFS

Cf. A257750 (Quasi-Carmichael numbers).

Sequence in context: A260867 A015219 A195545 * A228453 A327651 A319042

Adjacent sequences:  A270857 A270858 A270859 * A270861 A270862 A270863

KEYWORD

nonn,more,hard

AUTHOR

Tim Johannes Ohrtmann, Mar 24 2016

EXTENSIONS

a(7) from Dana Jacobsen, Apr 04 2016

STATUS

approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)