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A269704 Numbers k such that prime(k) == 1 (mod 8). 3
7, 13, 21, 24, 25, 30, 33, 44, 51, 53, 55, 60, 65, 68, 71, 79, 80, 84, 87, 88, 98, 104, 106, 108, 110, 113, 116, 122, 135, 136, 140, 148, 152, 158, 159, 162, 165, 169, 174, 176, 184, 189, 191, 196, 197, 199, 204, 209, 211, 216, 218, 223, 227, 234, 237, 245 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The asymptotic density of this sequence is 1/4 (by Dirichlet's theorem). - Amiram Eldar, Mar 01 2021

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

a(1) = 7 because prime(7) = 17 and 17 == 1 (mod 8).

MAPLE

Res:= NULL: count:= 0:

p:= 2:

for n from 2 while count < 100 do

  p:= nextprime(p);

  if p mod 8 = 1 then count:= count+1; Res:= Res, n fi

od:

Res; # Robert Israel, May 06 2019

MATHEMATICA

Select[Range[300], Mod[Prime[#], 8] == 1 &]

PROG

(MAGMA) [n: n in [1..500] | NthPrime(n) mod 8 eq 1];

(PARI) lista(nn) = for(n=1, nn, if(Mod(prime(n), 8)==1, print1(n, ", "))); \\ Altug Alkan, Mar 04 2016

CROSSREFS

The associated primes are in A007519.

Cf. similar sequences listed in A269703.

Sequence in context: A126621 A109331 A054858 * A157971 A135275 A304005

Adjacent sequences:  A269701 A269702 A269703 * A269705 A269706 A269707

KEYWORD

nonn,changed

AUTHOR

Vincenzo Librandi, Mar 04 2016

STATUS

approved

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Last modified March 9 03:35 EST 2021. Contains 341962 sequences. (Running on oeis4.)