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A186408 Numbers n such that there are 16 primes between 100*n and 100*n + 99. 21
2, 3, 6, 10, 42, 58, 194, 230, 12463, 8392963, 24662691, 37400476, 163061323, 205481131, 278399797, 313114319, 481863166, 494959102, 656914015, 776749247, 960655996, 980373049, 1097546872, 1156724143, 2013136112, 2245034146, 3416649829, 3606810631, 4141180699, 5928231877, 6569717174, 6594050440, 7240502155, 7492029097, 8995086259 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are 6699888 possible prime patterns for centuries having 16 primes. - Tim Johannes Ohrtmann, Aug 27 2015

LINKS

Table of n, a(n) for n=1..35.

EXAMPLE

2 is in this sequence because there are 16 primes between 200 and 299 (211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283 and 293).

PROG

(PARI) for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==16, print1(n", "))); \\ Charles R Greathouse IV, Feb 21 2011

(PARI) N=100; s=0; forprime(p=2, 4e9, if(p>N, if(s==16, 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-A186407 (1 to 15 primes), A186509 (17 primes).

Sequence in context: A274964 A054357 A056606 * A062527 A296444 A038752

Adjacent sequences:  A186405 A186406 A186407 * A186409 A186410 A186411

KEYWORD

nonn

AUTHOR

Tim Johannes Ohrtmann, Feb 20 2011

EXTENSIONS

a(9)-a(12) from Charles R Greathouse IV, Feb 21 2011

a(13)-a(35) from T. D. Noe, Feb 23 2011

STATUS

approved

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Last modified July 17 02:10 EDT 2019. Contains 325092 sequences. (Running on oeis4.)