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%I #28 Dec 30 2022 06:30:44
%S 1,9,67,437,441,2615,100349,100353,100359,637197,637305,27066969,
%T 27067049,27067101,27067113,27067115,179992839,179993001
%N Numbers k such that prime(k+1) == 2 (mod k).
%C Integers k such that A004649(k+1) = 2. - _Michel Marcus_, Dec 30 2022
%t bb={};Do[If[2==Mod[Prime[n+1], n], bb=Append[bb, n]], {n, 1, 200000}];bb
%t With[{nn=640000},Flatten[Position[Thread[{Range[nn],Prime[Range[2,nn+1]]}], _?(Mod[Last[#]-2,First[#]]==0&),{1},Heads->False]]] (* _Harvey P. Dale_, Sep 23 2021 *)
%o (Sage)
%o def A105287(max) :
%o terms = []
%o p = 3
%o for n in range(1, max+1) :
%o if (p - 2) % n == 0 : terms.append(n)
%o p = next_prime(p)
%o return terms
%o # _Eric M. Schmidt_, Feb 05 2013
%Y Cf. A004649, A105286, A105288, A105290, A105329, A105451.
%K nonn,more
%O 1,2
%A _Zak Seidov_, Apr 25 2005
%E First term inserted by _Eric M. Schmidt_, Feb 05 2013
%E More terms from _Harvey P. Dale_, May 04 2013
%E a(12)-a(18) from _Michel Marcus_, Dec 29 2022
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