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 A102343 Numbers n such that n*10^3+777 is prime. 0
 1, 2, 11, 19, 22, 26, 41, 43, 44, 47, 50, 53, 65, 67, 68, 71, 76, 79, 80, 83, 94, 97, 107, 110, 113, 115, 122, 124, 125, 131, 134, 136, 137, 145, 146, 152, 155, 158, 167, 169, 170, 173, 176, 181, 184, 199, 202, 211, 212, 226, 229, 232, 233, 250, 253, 254, 268, 272, 274, 281, 284, 286, 292, 295, 298, 299 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The sequence is infinite, because by Dirichlet's theorem there are infinitely many primes in the arithmetic sequence A*n+B (n=1,2,...) if A an B are relatively prime. [Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 27 2009] No term of the sequence is of form 3k, because the sum of digits of 10^3*3k+333=3*(10^3+259) is divisible by 3, violating the requirement of the definition. [Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 27 2009] LINKS EXAMPLE n=1: 1*10^3+777 = 1777 is prime, hence 1 is in the sequence. n=50: 50*10^3+777 = 50777 is prime, hence 50 is in the sequence. n=97: 97*10^3+777 = 97777 is prime, hence 97 is in the sequence. PROG (MAGMA) [ n: n in [0..300] | IsPrime(n*10^3+777) ]; (PARI) is(n)=isprime(n*10^3+777) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Cf. A157772, A102248, A159942. [Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 27 2009] Sequence in context: A121848 A074926 A066144 * A023173 A018443 A163058 Adjacent sequences:  A102340 A102341 A102342 * A102344 A102345 A102346 KEYWORD nonn,base,easy AUTHOR Parthasarathy Nambi, Feb 20 2005 EXTENSIONS Extended by Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 27 2009 Edited by R. J. Mathar, Apr 30 2009 More terms from Vincenzo Librandi, May 01 2009 STATUS approved

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Last modified May 12 09:16 EDT 2021. Contains 343821 sequences. (Running on oeis4.)