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 A062353 Primes of the form bbbbba... where a and b are digits. 3
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 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 LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..260 EXAMPLE 4441 is a member where a=1 and b = 4. MATHEMATICA 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 *) PROG (PARI) 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 CROSSREFS Cf. A061022. Sequence in context: A038618 A030475 A069676 * A077390 A069677 A069678 Adjacent sequences: A062350 A062351 A062352 * A062354 A062355 A062356 KEYWORD nonn,base,easy AUTHOR Amarnath Murthy, Jun 23 2001 EXTENSIONS More terms from Jason Earls, Jun 26 2001 Corrected and extended by Dean Hickerson, Jul 10 2001 STATUS approved

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Last modified July 23 23:47 EDT 2024. Contains 374575 sequences. (Running on oeis4.)