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%I #11 Oct 03 2021 04:47:14
%S 7,8,9,17,29,41,50,55,56,75,76,93,94,95,96,105,126,141,142,159,164,
%T 165,171,179,180,181,184,185,193,199,200,210,211,212,226,242,243,244,
%U 247,248,249,256,275,280,283,311,322,323,324,337,342,346,354,358,359
%N Numbers k such that 1/prime(k) has period prime(k) - 1 and 1/prime(k+1) has period prime(k+1) - 1.
%C Numbers k such that k and k+1 are both in A060257. - _Amiram Eldar_, Oct 03 2021
%H Amiram Eldar, <a href="/A060258/b060258.txt">Table of n, a(n) for n = 1..10000</a>
%t q[n_] := Module[{p = Prime[n]}, MultiplicativeOrder[10, p] == p - 1]; Select[Range[360], q[#] && q[#+1] &] (* _Amiram Eldar_, Oct 03 2021 *)
%Y Cf. A060257.
%K nonn
%O 1,1
%A _Jeff Burch_, Mar 23 2001
%E Data corrected by _Amiram Eldar_, Oct 03 2021