A178551 Primes with exactly two 2's.

223, 227, 229, 1223, 1229, 2027, 2029, 2129, 2203, 2207, 2213, 2237, 2239, 2243, 2251, 2267, 2269, 2273, 2281, 2287, 2293, 2297, 2423, 2521, 2621, 2729, 2927, 3221, 3229, 4229, 5227, 6221, 6229, 7229, 8221, 9221, 9227, 10223, 12203, 12211, 12239

Offset

1,1

Links

Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

Prog

(Python)
from sympy import isprime
print([i for i in range(10000) if str(i).count('2') == 2 and isprime(i)]) # Daniel Starodubtsev, Mar 29 2020

Crossrefs

Cf. A038618, A178550, A178552, A178553, A178554, A178555, A178556, A178557, A178558.

Sequence in context: A234623 A252956 A163653 * A105982 A243766 A153424

Adjacent sequences: A178548 A178549 A178550 * A178552 A178553 A178554

Keyword

nonn,base

Author

Lekraj Beedassy, May 29 2010

Status

approved