A061022 -id:A061022 - cp's OEIS frontend

A062353 Primes of the form bbbbba... where a and b are digits.

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 113, 223, 227, 229, 331, 337, 443, 449, 557, 661, 773, 881, 883, 887, 991, 997, 1117, 2221, 3331, 4441, 4447, 5557, 6661, 8887, 11113, 11117, 11119, 22229

Offset: 1

Amarnath Murthy, Jun 23 2001

Number of terms of n digits: 4, 21, 16, 8, 9, 8, 2, 8, 7, 3, 4, 5, 2, 2, 4, 0, 3, 4, 2, 3, 2, 2, 4, 1, 0, ..., . - Robert G. Wilson v, May 29 2011

			4441 is a member where a=1 and b = 4.

Charles R Greathouse IV, Table of n, a(n) for n = 1..260

Cf. A034845, A061022.

f[n_] := Select[ Union@ Flatten@ Table[ FromDigits@ Join[ Table[b, {n - 1}], {a}], {b, 9}, {a, {1, 3, 7, 9}}], PrimeQ]; f[1] = {2, 3, 5, 7}; Array[f, 5] // Flatten (* Robert G. Wilson v, May 29 2011 *)

print1("2, 3, 5, 7");for(n=2,20,forstep(k=10^n\9-1,10^n-9,10^n\9-1,for(m=k+1,k+9,if(isprime(m),print1(", "m))))) \\ Charles R Greathouse IV, May 29 2011

More terms from Jason Earls, Jun 26 2001

Corrected and extended by Dean Hickerson, Jul 10 2001

A383978 Primes with at least two identical trailing digits.

Original entry on oeis.org

11, 199, 211, 233, 277, 311, 433, 499, 577, 599, 677, 733, 811, 877, 911, 977, 1033, 1277, 1399, 1433, 1499, 1511, 1699, 1733, 1777, 1811, 1877, 1933, 1999, 2011, 2099, 2111, 2311, 2333, 2377, 2399, 2411, 2477, 2633, 2677, 2699, 2711, 2777, 2833, 2999, 3011, 3299

Offset: 1

Stefano Spezia, May 16 2025

Robert Israel, Table of n, a(n) for n = 1..10000

Cf. A131306, A383979, A384013, A384015.
Subsequence of A050758.
Cf. A061022 (variant).

select(isprime, [seq(seq(i*100 + j*11, j = [1,3,7,9]),i=0..100)]); # Robert Israel, May 17 2025

Select[Prime[Range[500]],Part[d=IntegerDigits[#],l=IntegerLength[#]]==Part[d,l-1] &]

from sympy import isprime
from itertools import count, islice
def agen(): # generator of terms
    yield from filter(isprime, (i+k for i in count(0, 100) for k in (11, 33, 77, 99)))
print(list(islice(agen(), 50))) # Michael S. Branicky, May 20 2025

cp's OEIS Frontend

A062353 Primes of the form bbbbba... where a and b are digits.

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