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A346990
Numbers occurring as divisors of 2^k + 3^k, k > 0.
1
1, 5, 7, 11, 13, 17, 25, 31, 35, 37, 41, 49, 55, 59, 61, 73, 77, 79, 83, 89, 97, 103, 107, 109, 113, 121, 125, 127, 131, 137, 149, 151, 155, 157, 169, 173, 175, 179, 181, 193, 199, 217, 223, 227, 229, 233, 241, 245, 251, 257, 271, 275, 277, 281, 289, 295, 313
OFFSET
1,2
COMMENTS
If n is a term, then so are all divisors of n. - Robert Israel, Dec 08 2022
LINKS
MAPLE
filter:= proc(n) local v;
if igcd(n, 6) <> 1 then return false fi;
q:= 3/2 mod n;
traperror(NumberTheory:-ModularLog(-1, q, n)) <> lasterror
end proc:
filter(1):= true:
select(filter, [$1..400]); # Robert Israel, Dec 08 2022
CROSSREFS
Sequence in context: A106059 A102386 A348936 * A038958 A109416 A132170
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Aug 11 2021
STATUS
approved