A060258 Numbers k such that 1/prime(k) has period prime(k) - 1 and 1/prime(k+1) has period prime(k+1) - 1.

7, 8, 9, 17, 29, 41, 50, 55, 56, 75, 76, 93, 94, 95, 96, 105, 126, 141, 142, 159, 164, 165, 171, 179, 180, 181, 184, 185, 193, 199, 200, 210, 211, 212, 226, 242, 243, 244, 247, 248, 249, 256, 275, 280, 283, 311, 322, 323, 324, 337, 342, 346, 354, 358, 359

Offset: 1

Author

Jeff Burch, Mar 23 2001

Keywords

• nonn

Comments

Numbers k such that k and k+1 are both in A060257. - Amiram Eldar, Oct 03 2021

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A060257.

Programs

Mathematica

q[n_] := Module[{p = Prime[n]}, MultiplicativeOrder[10, p] == p - 1]; Select[Range[360], q[#] && q[#+1] &] (* Amiram Eldar, Oct 03 2021 *)

Extensions

Data corrected by Amiram Eldar, Oct 03 2021