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A292021
Lucas-Carmichael numbers that are congruent to 1 (mod 4).
1
20705, 80189, 120581, 1162349, 7274249, 8734109, 10260809, 14658349, 49412285, 90393029, 105818129, 110066669, 125532329, 256074029, 362868329, 366648281, 395032609, 434886605, 503733257, 558705449, 563601257, 574342145, 640057109, 939989609, 962529749
OFFSET
1,1
COMMENTS
Most Lucas-Carmichael numbers are congruent to 3 (mod 4). Of the 9967 numbers less than 10^12 only 198 are congruent to 1 (mod 4).
Analogous to A185321 - Carmichael numbers that are congruent to 3 (mod 4).
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..198 (terms below 10^12)
MATHEMATICA
a=Select[Range[2, 10^6], !PrimeQ[#] && Union[Transpose[FactorInteger[#]][[2]]] == {1} && Union[Mod[# + 1, Transpose[FactorInteger[#]][[1]] + 1]]=={0} &] ; Select[a, Mod[#, 4]==1 &] (* after Richard Pinch and Jeffrey Shallit at A006972 *)
CROSSREFS
Intersection of A006972 and A016813.
Sequence in context: A107263 A372296 A237329 * A183631 A340175 A176771
KEYWORD
nonn
AUTHOR
Amiram Eldar, Sep 07 2017
STATUS
approved