A048891 Primes that are congruent to 1 mod n, where n is the index of the prime.

2, 3, 11, 13, 37, 43, 1087, 64591, 64601, 64661, 1304707, 3523969, 3524249, 9558541, 189963073, 189963091, 189963847, 189968887, 189969319, 189969337, 1394194181, 1394194481, 1394194561, 1394197381, 1394199221, 1394199241, 3779851321, 3779851363, 3779856571, 10246935931, 10246936019, 10246936481, 75370121689, 75370121857, 75370122409, 75370125409, 75370126441

Offset: 1

Author

Jud McCranie

Keywords

• nonn

Comments

Based on problem by G. L. Honaker, Jr.

A subsequence of A073465. - Ivan N. Ianakiev, Aug 06 2019

Examples

			13 is the 6th prime and 13 == 1 mod 6.
		

Links

• Giovanni Resta, Table of n, a(n) for n = 1..94

Crossrefs

Cf. A000040, A023143, A045924, A052013.

Programs

Mathematica

f[p_,n_]:=Mod[p,n]==0; lst={};Do[p=Prime[n];If[f[p-1,n],AppendTo[lst,p]],{n,10!}];lst (* Vladimir Joseph Stephan Orlovsky, Dec 08 2009 *)

PARI

lista(nn) = forprime(p=1, nn, if (Mod(p, primepi(p)) == 1, print1(p, ", "))); \\ Michel Marcus, Jan 08 2015; Aug 06 2019

Formula

A087611(a(n)) = 0. - Reinhard Zumkeller, Sep 11 2003

a(n) = A000040(A023143(n)). - Zak Seidov, Feb 19 2015

Extensions

More terms from Zak Seidov, Feb 19 2015

Terms a(33)-a(37) sorted into correct order by Giovanni Resta, Feb 23 2020