

A346569


Carmichael numbers (A002997) k such that A003961(k) is also a Carmichael number.


2



938531360353681, 6178246534322281, 518705522457928921, 7019247908645553241, 16242056799655920481, 94812683932464811561, 94986212971063089241, 408133613144935002601, 418441276466266605481, 453648717063017803081, 556606627235843071681, 1140359076998537247001
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OFFSET

1,1


COMMENTS

Each of the first 17 terms has 3 distinct prime divisors. [updated Apr 22 2024]
a(6) <= 94812683932464811561. A term with 4 prime factors is 9584146525723596902470058833132261.  Daniel Suteu, Jul 24 2021


LINKS



EXAMPLE

938531360353681 = 53881 * 107761 * 161641 is a term since it is a Carmichael number, and A003961(938531360353681) = 53887 * 107773 * 161659 = 938844932257009 is also a Carmichael number.


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



