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A141711
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Carmichael numbers with more than 3 prime factors.
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8
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41041, 62745, 63973, 75361, 101101, 126217, 172081, 188461, 278545, 340561, 449065, 552721, 656601, 658801, 670033, 748657, 825265, 838201, 852841, 997633, 1033669, 1050985, 1082809, 1569457, 1773289, 2100901, 2113921, 2433601
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OFFSET
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1,1
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COMMENTS
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Sequence A087788 gives Carmichael numbers with exactly 3 prime factors; since they cannot have fewer (cf. references in A002997), this sequence is the complement of A087788 in A002997.
The terms preceding a(17) = 825265 = A006931(5) have exactly 4 prime factors. See A112428 - A112432 for Carmichael numbers with exactly 5, ..., 9 prime factors. - M. F. Hasler, Apr 14 2015
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LINKS
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Amiram Eldar, Table of n, a(n) for n = 1..10000
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FORMULA
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A141711 = A002997 \ A087788 = A074379 U A112428 U A112429 U A112430 U A112431 U A112432 U ...
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EXAMPLE
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a(17)=825265 is the least Carmichael number having more than 4 divisors, thus the sequence differs from A074379 only from that term on.
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MATHEMATICA
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ok[n_] := Divisible[n - 1, CarmichaelLambda[n]] && Length[FactorInteger[n]] > 3; Select[ Range[3*10^6], ok] (* Jean-François Alcover, Sep 23 2011 *)
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PROG
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(PARI) A2997=readvec("b002997.gp"); A002997(n)=A2997[n]; for( n=1, 100, omega( A002997(n) ) > 3 & print1( A002997(n)", "))
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CROSSREFS
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Cf. A002997, A087788, A074379, A112428 - A112432, A006931.
Sequence in context: A033532 A173361 A047828 * A074379 A237395 A252121
Adjacent sequences: A141708 A141709 A141710 * A141712 A141713 A141714
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KEYWORD
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nonn
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AUTHOR
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M. F. Hasler, Jul 01 2008
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STATUS
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approved
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