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Numbers k such that there are 16 primes between 100*k and 100*k + 99.
23

%I #36 Mar 22 2024 03:47:35

%S 2,3,6,10,42,58,194,230,12463,8392963,24662691,37400476,163061323,

%T 205481131,278399797,313114319,481863166,494959102,656914015,

%U 776749247,960655996,980373049,1097546872,1156724143,2013136112,2245034146,3416649829,3606810631,4141180699,5928231877,6569717174,6594050440,7240502155,7492029097,8995086259

%N Numbers k such that there are 16 primes between 100*k and 100*k + 99.

%C There are 6699888 possible prime patterns for centuries having 16 primes. - _Tim Johannes Ohrtmann_, Aug 27 2015

%H Brian Kehrig, <a href="/A186408/b186408.txt">Table of n, a(n) for n = 1..1000</a>

%e 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).

%o (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

%o (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

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

%Y Cf. A181098 (no primes), A186393-A186407 (1 to 15 primes), A186509 (17 primes), A361723 (18 primes).

%K nonn

%O 1,1

%A _Tim Johannes Ohrtmann_, Feb 20 2011

%E a(9)-a(12) from _Charles R Greathouse IV_, Feb 21 2011

%E a(13)-a(35) from _T. D. Noe_, Feb 23 2011