This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A111436 Least multiple of n such that every partial concatenation followed by a 1 is prime. 0
 1, 8, 3, 4, 5, 78, 28, 32, 36, 40, 176, 528, 624, 280, 30, 144, 1088, 432, 1273, 120, 1869, 440, 3427, 1632, 2000, 2080, 1701, 2268, 10179, 480, 5270, 2464, 660, 1632, 4970, 1044, 222, 2242, 351, 3120, 5576, 798, 1032, 5896, 630, 230, 1081, 8064, 9261, 9500 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE 11, 181, 183, 1834, 183451, etc. are all prime. MATHEMATICA s = ""; Do[k = 1; While[ !PrimeQ[ToExpression[s <> ToString[k*n] <> "1"]], k++ ]; Print[k*n]; s = s <> ToString[k*n], {n, 1, 100}] (* Ryan Propper, Sep 21 2005 *) CROSSREFS Sequence in context: A070597 A222232 A091895 * A014549 A021549 A013665 Adjacent sequences:  A111433 A111434 A111435 * A111437 A111438 A111439 KEYWORD base,nonn AUTHOR Amarnath Murthy, Aug 03 2005 EXTENSIONS More terms from Ryan Propper, Sep 21 2005 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 April 26 08:53 EDT 2019. Contains 322472 sequences. (Running on oeis4.)