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 A276046 Numbers n such that (26*10^n - 23)/3 is prime. 0
 1, 2, 10, 16, 78, 97, 125, 138, 192, 242, 290, 373, 408, 467, 583, 892, 899, 1709, 1944, 2154, 3618, 5225, 8974, 9377, 12504, 20042, 49106, 63073, 92152 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For n>1, numbers such that the digit 8 followed by n-2 occurrences of the digit 6 followed by the digits 59 is prime (see Example section). a(30) > 10^5. LINKS Makoto Kamada, Factorization of near-repdigit-related numbers. Makoto Kamada, Search for 86w59. EXAMPLE 2 is in this sequence because (26*10^2 - 23)/3 = 859 is prime. Initial terms and primes associated: a(1) = 1, 79; a(2) = 2, 859; a(3) = 10, 86666666659; a(4) = 16, 86666666666666659, etc. MATHEMATICA Select[Range[0, 100000], PrimeQ[(26*10^# - 23)/3] &] PROG (PARI) is(n)=ispseudoprime((26*10^n-23)/3) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Cf. A056654, A268448, A269303, A270339, A270613, A270831, A270890, A270929, A271269. Sequence in context: A046036 A131474 A249153 * A268481 A009387 A305093 Adjacent sequences:  A276043 A276044 A276045 * A276047 A276048 A276049 KEYWORD nonn,more AUTHOR Robert Price, Aug 17 2016 STATUS approved

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Last modified June 16 12:38 EDT 2019. Contains 324152 sequences. (Running on oeis4.)