A186405 Numbers k such that there are 13 primes between 100*k and 100*k + 99.

19, 36, 54, 55, 62, 69, 86, 88, 96, 119, 124, 156, 166, 174, 201, 211, 215, 220, 238, 240, 308, 320, 323, 329, 355, 408, 412, 416, 427, 442, 544, 569, 606, 616, 633, 636, 674, 713, 775, 798, 806, 832, 875, 888, 900, 923, 1098

Offset

1,1

Comments

There are 25913910 possible prime patterns for centuries having 13 primes. - Tim Johannes Ohrtmann, Aug 27 2015

Links

T. D. Noe, Table of n, a(n) for n = 1..1000

Example

19 is in this sequence because there are 13 primes between 1900 and 1999 (1901, 1907, 1913, 1931, 1933, 1949, 1951, 1973, 1979, 1987, 1993, 1997 and 1999).

Prog

(PARI) for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==13, print1(n", "))); \\ Charles R Greathouse IV, Feb 21 2011
(PARI) N=100; s=0; forprime(p=2, 4e9, if(p>N, if(s==13, print1((N\100)-1, ", ")); s=1; N=100*(p\100+1), s++)) \\ Charles R Greathouse IV, Feb 21 2011

Crossrefs

Cf. A038822 (number of primes between 100n and 100n+99), A186311 (first occurrences).

Cf. A181098 (no primes), A186393-A186408 (1 to 16 primes), A186509 (17 primes), A361723 (18 primes).

Sequence in context: A333414 A146579 A146454 * A240238 A368833 A352885

Adjacent sequences: A186402 A186403 A186404 * A186406 A186407 A186408

Keyword

nonn

Author

Tim Johannes Ohrtmann, Feb 20 2011

Status

approved