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A110885
Lucas-Carmichael numbers that are not congruent to 11 (mod 12).
2
399, 5719, 20705, 80189, 120581, 162687, 482143, 663679, 1162349, 7274249, 8734109, 9486399, 10260809, 10397407, 14658349, 14970499, 25603599, 29010079, 32869759, 49412285, 77801359, 90393029, 95972799, 99467679, 105818129, 110066669, 125532329, 126325399
OFFSET
1,1
COMMENTS
There are 9967 Lucas-Carmichael numbers less than 10^12, and all but 332 are congruent to 11 (mod 12).
LINKS
EXAMPLE
5719=7*19*43=7 mod 12.
MAPLE
with(numtheory); LC:=[]: for z from 1 to 1 do for m from 1 to 2000000 do n:=2*m+1; if not(isprime(n)) and issqrfree(n) then PF:=factorset(n); lcb:=true; for x in PF do if (n+1) mod (x+1) > 0 then lcb:=false fi od; if lcb then LC:=[op(LC), n]; fi; fi; #not od; #m od; #z select(proc(z) not(z mod 12 = 11) end, LC);
CROSSREFS
Cf. A006972.
Sequence in context: A369246 A065767 A166915 * A249408 A216928 A283384
KEYWORD
nonn
AUTHOR
Walter Kehowski, Sep 19 2005
EXTENSIONS
a(10) onward from Robert G. Wilson v, Feb 12 2015
STATUS
approved