cp's OEIS Frontend

A116658 Numbers k such that prime(k) == 13 (mod k).

%I A116658 #20 Feb 11 2021 22:56:05
%S A116658 1,2,6,12,22,40,42,84,86,90,193,2712,16056,16058,40077,40123,40124,
%T A116658 40125,251720,251766,251769,251787,637332,10553432,10553435,10553501,
%U A116658 10553568,10553817,10553826,27067042,27067132,69709722,179993160,465769803
%N A116658 Numbers k such that prime(k) == 13 (mod k).
%C A116658 Starting with a(5), positions of 13 in A004648. - corrected by _Eric M. Schmidt_, Feb 05 2013
%t A116658 NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; p = 1; Do[ If[ Mod[p = NextPrim[p], n] == 13, Print[n]], {n, 10^9}] (* _Robert G. Wilson v_, Feb 22 2006 *)
%o A116658 (Sage)
%o A116658 def A116658(max) :
%o A116658     terms = []
%o A116658     p = 2
%o A116658     for n in range(1, max+1) :
%o A116658         if (p - 13) % n == 0 : terms.append(n)
%o A116658         p = next_prime(p)
%o A116658     return terms
%o A116658 # _Eric M. Schmidt_, Feb 05 2013
%Y A116658 Cf. A004648; A023143 - A023152, A116657, A116677, A116658, A116659: prime(n) == m (mod n), m=1..14.
%K A116658 nonn
%O A116658 1,2
%A A116658 _Zak Seidov_, Feb 21 2006
%E A116658 a(24)-a(34) from _Robert G. Wilson v_, Feb 22 2006
%E A116658 First four terms inserted by _Eric M. Schmidt_, Feb 05 2013