A110885 Lucas-Carmichael numbers that are not congruent to 11 (mod 12).

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

Amiram Eldar, Table of n, a(n) for n = 1..2067 (terms below 10^15, calculated from Daniel Suteu's file at A006972; terms 1..333 from Robert G. Wilson v)

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

Adjacent sequences: A110882 A110883 A110884 * A110886 A110887 A110888

Keyword

nonn

Author

Walter Kehowski, Sep 19 2005

Extensions

a(10) onward from Robert G. Wilson v, Feb 12 2015

Status

approved