This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 8 01:57 EST 2019. Contains 329850 sequences. (Running on oeis4.)