A343115 Numbers k such that k^2 divides 5^k - 3^k - 2^k.

1, 2, 3, 4, 5, 6, 8, 12, 15, 19, 24, 95, 361, 876

Offset

1,2

Comments

Are there only finitely many such numbers?

Primes in the sequence are A130076.

Next term, if it exists, exceeds 5*10^8. - Jon E. Schoenfield, May 07 2021

Links

Table of n, a(n) for n=1..14.

Maple

q:= k-> is(0=5&^k-3&^k-2&^k mod k^2):
select(q, [$1..1000])[];  # Alois P. Heinz, May 07 2021

Mathematica

Select[Range[1000], Mod[PowerMod[2, #, #^2] + PowerMod[3, #, #^2], #^2] == PowerMod[5, #, #^2] &] (* Amiram Eldar, Apr 05 2021 *)

Crossrefs

Cf. A130072, A130073, A130076.

Sequence in context: A173288 A134677 A104419 * A092232 A060322 A143285

Adjacent sequences: A343112 A343113 A343114 * A343116 A343117 A343118

Keyword

nonn,more

Author

Thomas Ordowski, Apr 05 2021

Status

approved