cp's OEIS Frontend

A105329 Numbers k such that prime(k+1) == 5 (mod k).

%I A105329 #24 Aug 31 2024 22:02:06
%S A105329 1,2,6,7,12,14,181,1053,1057,2614,40089,40114,40117,40119,100346,
%T A105329 100352,100358,251707,251742,251743,251754,251757,1617173,4124458,
%U A105329 10553513,27067262,27067272,179992922,179992932,179993012,179993172,3140421806,3140421838,3140421866,3140421872,55762149076,145935689366
%N A105329 Numbers k such that prime(k+1) == 5 (mod k).
%C A105329 There are no further terms up to 215000000. - _Farideh Firoozbakht_, May 13 2005
%C A105329 Integers k such that A004649(k+1) = 5. - _Michel Marcus_, Dec 30 2022
%t A105329 Do[If[5 == Mod[Prime[n + 1], n], bb = Append[bb, n]], {n, 1, 251758}];
%t A105329 bb={};Do[If[5 == Mod[Prime[n + 1], n], bb = Append[bb, n]], {n, 1, 251758}];bb  (* _Farideh Firoozbakht_, May 13 2005 *)
%o A105329 (Sage)
%o A105329 def A105329(max) :
%o A105329     terms = []
%o A105329     p = 3
%o A105329     for n in range(1, max+1) :
%o A105329         if (p - 5) % n == 0 : terms.append(n)
%o A105329         p = next_prime(p)
%o A105329     return terms
%o A105329 # _Eric M. Schmidt_, Feb 05 2013
%Y A105329 Cf. A004649, A105286, A105287, A105288, A105290, A105451.
%K A105329 nonn
%O A105329 1,2
%A A105329 _Zak Seidov_, Apr 30 2005
%E A105329 More terms from _Farideh Firoozbakht_, May 13 2005
%E A105329 First two terms inserted by _Eric M. Schmidt_, Feb 05 2013
%E A105329 a(28)-a(29) corrected, a(30)-a(37) added by _Max Alekseyev_, Aug 31 2024