A346990 Numbers occurring as divisors of 2^k + 3^k, k > 0.

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

Author

Hugo Pfoertner, Aug 11 2021

Keywords

• nonn

Comments

If n is a term, then so are all divisors of n. - Robert Israel, Dec 08 2022

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A007689, A005056.

Programs

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