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Primes of the form 256*k + 1.
9

%I #25 Nov 01 2022 12:22:24

%S 257,769,3329,7681,7937,9473,10753,11777,12289,13313,14081,14593,

%T 15361,17921,18433,19457,22273,23041,23297,25601,26113,26881,30977,

%U 31489,32257,36097,36353,37633,37889,39937,40193,40961,41729,43777,45569,46337,49409,49921

%N Primes of the form 256*k + 1.

%C Odd primes p such that -1 is a 128th power mod p. - _Eric M. Schmidt_, Mar 27 2014

%H Reinhard Zumkeller, <a href="/A208178/b208178.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) ~ 128n log n. - _Charles R Greathouse IV_, Nov 01 2022

%t Select[256 Range[195] + 1, PrimeQ]

%o (PARI) for(n=1,195,r=256*n+1; if(isprime(r), print1(r", ")));

%o (Magma) [ p: p in PrimesUpTo(50000) | p mod 256 eq 1 ];

%o (Haskell)

%o a208178 n = a208178_list !! (n-1)

%o a208178_list = filter ((== 1) . a010051) [1,257..]

%o -- _Reinhard Zumkeller_, Mar 06 2012

%Y Cf. A065091, A002144, A007519, A094407, A133870, A142925, A208177, A076339.

%K nonn,easy

%O 1,1

%A _Bruno Berselli_, Feb 25 2012