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A142024 Primes congruent to 20 mod 31. 1
113, 547, 733, 857, 919, 1229, 1291, 1601, 1663, 1787, 1973, 2221, 2531, 2593, 2903, 3089, 3461, 3709, 3833, 4019, 4391, 4639, 5011, 5197, 5507, 5569, 5693, 5879, 6871, 7057, 7243, 8111, 8297, 8669, 8731, 9041, 9103, 9227, 9413, 9661, 10343, 10529, 11087 (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) ~ 30n log n. - Charles R Greathouse IV, Jul 03 2016

MATHEMATICA

Select[Range[20, 20000, 31], PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Apr 30 2011 *)

Select[Prime[Range[1400]], Mod[#, 31]==20&] (* Harvey P. Dale, Jul 30 2020 *)

PROG

(MAGMA) [p: p in PrimesUpTo(12000) | p mod 31 eq 20 ]; // Vincenzo Librandi, Aug 17 2012

(PARI) is(n)=isprime(n) && n%31==20 \\ Charles R Greathouse IV, Jul 03 2016

CROSSREFS

Cf. A000040, A142005, A142006, A142023.

Sequence in context: A118506 A341230 A109563 * A300964 A077287 A087294

Adjacent sequences:  A142021 A142022 A142023 * A142025 A142026 A142027

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Jul 11 2008

STATUS

approved

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Last modified December 9 08:41 EST 2021. Contains 349627 sequences. (Running on oeis4.)