The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A135377 Smallest n-primeval prime, i.e., minimal prime number containing all A006880(n) primes < 10^n embedded in it as permutations of some of its substrings. 1
 2357, 1123465789, 10112233445566788997, 100111222333444555666777998889, 1000111222233334444555666777798889899, 100001111222233333444445555566666777778888999989 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(1) - a(4) were computed by Mike Keith in 2008 and a(4) - a(31) by Jérôme STORTI in 2002. LINKS M. Keith, Integers containing many embedded primes EXAMPLE Mike Keith's website uses a shorthand notation for these numbers. The 4-primeval prime 100111222333444555666777998889 is written in this notation as (1) 2 3 3 3 3 3 3 3 0 998889. The (1) represents the leading 1 digit (which will always be present). The next number says how many consecutive 0's follow the leading 1 and the next says how many consecutive 1's follow that and so on up to the number of consecutive 8's. The final grouping explicitly shows how the last group of 8's and 9's are arranged. The following are the n-primeval primes as found by Jérôme STORTI in this notation: 5 (1) 3 3 4 4 4 3 3 4 0 98889899 6 (1) 4 4 4 5 5 5 5 5 4 999989 7 (1) 5 5 5 6 5 5 5 6 3 98899999 8 (1) 5 6 7 7 6 7 7 7 6 98999999 9 (1) 7 7 8 8 8 7 8 8 6 9999989899 10 (1) 8 8 8 9 9 9 9 9 7 9999899999 11 (1) 8 9 10 10 10 9 10 10 6 9889989999999 12 (1) 10 10 10 11 11 11 10 11 9 9998999999899 13 (1) 10 11 11 12 11 12 11 12 9 99899999999899 14 (1) 11 13 13 13 12 12 12 13 11 989999989999999 15 (1) 12 13 14 14 13 14 13 14 12 9999999988999999 16 (1) 13 14 14 15 14 14 14 15 12 99999999999999889 17 (1) 14 15 15 16 15 15 15 16 14 998999999999998999 18 (1) 16 17 17 17 16 17 17 17 14 9989999999999899999 19 (1) 17 18 17 18 17 17 17 18 15 988999999899999999999 20 (1) 17 19 18 19 19 18 19 19 16 999999998999999999989 21 (1) 18 19 19 20 19 19 20 20 17 9899999999999999998999 22 (1) 18 20 20 21 20 21 21 21 18 99998999999999999998999 23 (1) 21 23 21 22 21 21 22 22 19 999999889999999999999999 24 (1) 20 22 22 23 22 22 22 23 21 999999999999999989999999 25 (1) 23 23 23 24 23 23 23 24 22 9999999999999999998999999 26 (1) 23 24 24 25 25 25 24 25 22 999999999999999999899999989 27 (1) 24 25 25 26 25 25 25 26 23 9999999998999999999999998999 28 (1) 25 26 27 27 27 26 27 27 25 9999899999999999999999999999 29 (1) 25 27 27 28 27 27 27 28 25 999999989999999999999999999989 30 (1) 26 29 28 29 29 28 28 29 27 999999999999998999999999999999 31 (1) 28 29 29 30 29 29 29 30 27 99999889999999999999999999999999 a(2) = 1123465789 because this is the smallest prime out of which each of the first 25 primes below 10^2, viz. 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 can be formed using its digits. CROSSREFS Cf. A072857, A039993, A134649. Sequence in context: A132904 A030473 A134649 * A081208 A250990 A269483 Adjacent sequences:  A135374 A135375 A135376 * A135378 A135379 A135380 KEYWORD nonn,base AUTHOR Lekraj Beedassy, Dec 09 2007 EXTENSIONS Link fixed by Charles R Greathouse IV, Aug 13 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 January 27 17:58 EST 2020. Contains 331296 sequences. (Running on oeis4.)