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 A275284 Numbers n such that (29*10^n - 41)/3 is prime. 0
 1, 2, 5, 7, 13, 16, 55, 61, 65, 98, 134, 296, 354, 527, 901, 1206, 1916, 2899, 3725, 4709, 7529, 8942, 12050, 12880, 15516, 25976, 62030 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For n>1, numbers n such that the digit 9 followed by n-2 occurrences of the digit 6 followed by the digits 53 is prime (see Example section). a(28) > 10^5. LINKS Makoto Kamada, Factorization of near-repdigit-related numbers. Makoto Kamada, Search for 96w53. EXAMPLE 5 is in this sequence because (29*10^5 - 41)/3 = 966653 is prime. Initial terms and primes associated: a(1) = 1, 83; a(2) = 2, 953; a(3) = 5, 966653; a(4) = 7, 96666653; a(5) = 13, 96666666666653, etc. MATHEMATICA Select[Range[0, 100000], PrimeQ[(29*10^# - 41)/3] &] PROG (PARI) lista(nn) = for(n=1, nn, if(ispseudoprime((29*10^n-41)/3), print1(n, ", "))); \\ Altug Alkan, Jul 21 2016 CROSSREFS Cf. A056654, A268448, A269303, A270339, A270613, A270831, A270890, A270929, A271269. Sequence in context: A065897 A293762 A161889 * A261123 A336451 A249330 Adjacent sequences:  A275281 A275282 A275283 * A275285 A275286 A275287 KEYWORD nonn,more AUTHOR Robert Price, Jul 21 2016 STATUS approved

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Last modified September 23 16:41 EDT 2020. Contains 337315 sequences. (Running on oeis4.)