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A268859 Prime numbers ending in 21. 3
421, 521, 821, 1021, 1321, 1621, 1721, 2221, 2521, 2621, 3121, 3221, 3821, 4021, 4421, 4621, 4721, 5021, 5521, 5821, 6121, 6221, 6421, 6521, 7121, 7321, 7621, 8221, 8521, 8821, 9221, 9421, 9521, 9721, 10321, 11321, 11621, 11821, 12421, 12721, 12821, 13121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..42.

MAPLE

A268859:=n->`if`(isprime(n) and n mod 100 = 21, n, NULL): seq(A268859(n), n=1..5*10^4); # Wesley Ivan Hurt, Apr 02 2016

MATHEMATICA

Select[Table[21 + 100 i, {i, 0, 10^3}], ProvablePrimeQ[#] &]

PROG

(MAGMA) [n: n in PrimesUpTo(15000) | n mod 100 eq 21]; // Vincenzo Librandi, Feb 15 2016

(PARI) lista(nn) = {for(n=1, nn, if (isprime(p=100*n+21), print1(p, ", ")); ); } \\ Michel Marcus, Feb 20 2016

(Python)

from sympy import isprime

for n in range(421, 15000, 100):

    if(isprime(n)):print(n)

# Soumil Mandal, Apr 03 2016

CROSSREFS

Cf. A268858, A268860.

Sequence in context: A014890 A159589 A031784 * A051648 A217497 A333640

Adjacent sequences:  A268856 A268857 A268858 * A268860 A268861 A268862

KEYWORD

nonn,base

AUTHOR

Soumadeep Ghosh, Feb 14 2016

STATUS

approved

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Last modified April 7 19:49 EDT 2020. Contains 333306 sequences. (Running on oeis4.)