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

%I #7 Feb 25 2020 05:35:18

%S 2,379,389,9559969,9559999,9560119,9560149,514274011,3779851261,

%T 204475055129,81744303090431,241849345578327127,241849345578334537,

%U 241849345578337111,241849345578359263,241849345578372913,241849345578373303,97199410027250043229,97199410027250048629,97199410027250052679

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

%t Prime@ Select[Range[10^6], Mod[Prime[#] - 4, #] == 0 &] (* _Giovanni Resta_, Feb 25 2020 *)

%Y Cf. A023146, A048891, A171430.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Dec 08 2009

%E Missing a(1) and a(8)-a(20) from _Giovanni Resta_, Feb 23 2020