A110889 Carmichael numbers that are not == 1 mod 12. There are 69 Carmichael numbers out to 2*m+1, m=2*10^6 and all but the above 9 are 1 mod 12.

561, 2465, 8911, 62745, 162401, 656601, 1024651, 1152271, 1909001, 5444489, 5481451, 10267951, 11921001, 14913991, 19384289, 26719701, 45318561, 64377991, 67902031, 84350561, 139952671, 151530401, 174352641, 178482151, 221884001, 230996949, 275283401, 368113411, 395044651

Offset

1,1

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..25567

Example

8911=7*19*67=5 mod 12.

Maple

with(numtheory); CM:=[]: 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); cmb:=true; for x in PF do if (n-1) mod (x-1) > 0 then cmb:=false fi od; if cmb then CM:=[op(CM), n]; fi; fi; #not od; #m od; #z select(proc(z) not(z mod 12 = 1) end, CM);

Crossrefs

Cf. A002997.

Sequence in context: A290805 A217465 A097130 * A205947 A290692 A293622

Adjacent sequences: A110886 A110887 A110888 * A110890 A110891 A110892

Keyword

nonn

Author

Walter Kehowski, Sep 20 2005

Extensions

a(12)-a(29) from Charles R Greathouse IV, Nov 12 2015

Status

approved