A023146 -id:A023146 - cp's OEIS frontend

A092046 Numbers n such that prime(n) == -4 (mod n).

1, 3, 5, 7, 9, 67, 441, 2615, 637237, 637329, 4124703, 27067119, 179993017, 1208198617, 8179002101, 55762149071, 55762149091

Offset: 1

Robert G. Wilson v, Feb 18 2004

nonn

Cf. A023146, A045924, A092044, A092045, A092047, A092048, A092049, A092050, A092051, A092052.

NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; p = 1; Do[ If[ Mod[p = NextPrim[p], n] == n - 4, Print[n]], {n, 1, 10^9}]

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

a(13)-a(17) from Robert G. Wilson v, Feb 22 2006

A171431 Primes that are congruent to 4 mod n, where n is the index of the prime.

Original entry on oeis.org

2, 379, 389, 9559969, 9559999, 9560119, 9560149, 514274011, 3779851261, 204475055129, 81744303090431, 241849345578327127, 241849345578334537, 241849345578337111, 241849345578359263, 241849345578372913, 241849345578373303, 97199410027250043229, 97199410027250048629, 97199410027250052679

Offset: 1

Vladimir Joseph Stephan Orlovsky, Dec 08 2009

nonn

Cf. A023146, A048891, A171430.

Prime@ Select[Range[10^6], Mod[Prime[#] - 4, #] == 0 &] (* Giovanni Resta, Feb 25 2020 *)

Missing a(1) and a(8)-a(20) from Giovanni Resta, Feb 23 2020

cp's OEIS Frontend

A092046 Numbers n such that prime(n) == -4 (mod n).

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