This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A186404 #31 Mar 22 2024 03:45:13 %S A186404 11,15,17,18,28,30,37,45,46,47,50,56,60,67,68,76,85,91,98,101,103,106, %T A186404 118,122,125,126,129,131,136,137,144,145,148,151,152,153,157,160,164, %U A186404 169,173,199,203,207,221,226,235,236,241 %N A186404 Numbers k such that there are 12 primes between 100*k and 100*k + 99. %C A186404 There are 27836859 possible prime patterns for centuries having 12 primes. - _Tim Johannes Ohrtmann_, Aug 27 2015 %H A186404 T. D. Noe, <a href="/A186404/b186404.txt">Table of n, a(n) for n = 1..1000</a> %e A186404 11 is in this sequence because there are 12 primes between 1100 and 1199 (1103, 1109, 1117, 1123, 1129, 1151, 1153, 1163, 1171, 1181, 1187 and 1193). %t A186404 Select[Range[250],PrimePi[100#+99]-PrimePi[100#]==12&] (* _Harvey P. Dale_, Sep 20 2011 *) %o A186404 (PARI) for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==12, print1(n", "))); \\ _Charles R Greathouse IV_, Feb 21 2011 %o A186404 (PARI) N=100; s=0; forprime(p=2, 4e9, if(p>N, if(s==12, print1((N\100)-1, ", ")); s=1; N=100*(p\100+1), s++)) \\ _Charles R Greathouse IV_, Feb 21 2011 %Y A186404 Cf. A038822 (number of primes between 100n and 100n+99), A186311 (first occurrences). %Y A186404 Cf. A181098 (no primes), A186393-A186408 (1 to 16 primes), A186509 (17 primes), A361723 (18 primes). %K A186404 nonn %O A186404 1,1 %A A186404 _Tim Johannes Ohrtmann_, Feb 20 2011