A268859 Prime numbers ending in 21.

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

Offset: 1

Author

Soumadeep Ghosh, Feb 14 2016

Keywords

• nonn
• base

Crossrefs

Cf. A268858, A268860.

Programs

Magma

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

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[#] &]

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