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A186405
Numbers k such that there are 13 primes between 100*k and 100*k + 99.
1
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
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
KEYWORD
nonn
AUTHOR
STATUS
approved