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Numbers n such that prime(n) == -3 (mod n).
11

%I #8 Mar 29 2023 13:04:01

%S 1,2,25,26,68,1054,1058,6472,251723,4124468,69709727,69709942,

%T 465769817,465769835,1208198860,8179002154,8179002176,8179002178,

%U 145935689360,145935689369,145935689392,145935689393

%N Numbers n such that prime(n) == -3 (mod n).

%t NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; p = 1; Do[ If[ Mod[p = NextPrim[p], n] == n - 3, Print[n]], {n, 1, 10^9}]

%t Join[{1,2},Select[Range[5 10^6],Mod[Prime[#],#]==#-3&]] (* _Harvey P. Dale_, Mar 29 2023 *)

%Y Cf. A023145, A045924, A092044, A092046, A092047, A092048, A092049, A092050, A092051, A092052.

%K nonn

%O 1,2

%A _Robert G. Wilson v_, Feb 18 2004

%E Corrected by Mohammed Bouayoun (bouyao(AT)wanadoo.fr), Feb 20 2004

%E a(13)-a(22) from _Robert G. Wilson v_, Feb 22 2006