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A141943 Primes congruent to 21 mod 25. 1
71, 271, 421, 521, 571, 821, 971, 1021, 1171, 1321, 1471, 1571, 1621, 1721, 1871, 2221, 2371, 2521, 2621, 2671, 2971, 3121, 3221, 3271, 3371, 3571, 3671, 3821, 4021, 4271, 4421, 4621, 4721, 4871, 5021, 5171, 5471, 5521, 5821, 6121, 6221, 6271, 6421, 6521 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

FORMULA

a(n) ~ 20n log n. - Charles R Greathouse IV, Jul 03 2016

MATHEMATICA

Select[Range[21, 20000, 25], PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Jun 15 2011 *)

PROG

(MAGMA) [p: p in PrimesUpTo(8000) | p mod 25 eq 21 ]; // Vincenzo Librandi, Aug 16 2012

(PARI) is(n)=isprime(n) && n%25==21 \\ Charles R Greathouse IV, Jul 03 2016

CROSSREFS

Cf. A000040.

Sequence in context: A033240 A298103 A293395 * A167441 A140856 A114992

Adjacent sequences:  A141940 A141941 A141942 * A141944 A141945 A141946

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Jul 11 2008

STATUS

approved

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Last modified November 26 12:37 EST 2020. Contains 338639 sequences. (Running on oeis4.)