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 A186394 #34 Mar 22 2024 03:47:44 %S A186394 3020,3709,4484,4617,4806,4921,5072,5423,5616,6041,6194,6231,6452, %T A186394 6485,6683,6828,7101,7365,7454,7532,7839,8096,8157,8728,8738,9221, %U A186394 9486,9635,9796,10152,10506,10720,10852,11261,11621,11736,11953,11992 %N A186394 Numbers k such that there are 2 primes between 100*k and 100*k + 99. %C A186394 There are 780 possible prime patterns for centuries having 2 primes. - _Tim Johannes Ohrtmann_, Aug 27 2015 %H A186394 T. D. Noe, <a href="/A186394/b186394.txt">Table of n, a(n) for n = 1..1000</a> %e A186394 3020 is in this sequence because there are 2 primes between 302000 and 302099 (302009 and 302053). %o A186394 (Sage) %o A186394 def is_A186394(n): %o A186394 np0 = next_prime(next_prime(100*n)) %o A186394 np1 = next_prime(np0) %o A186394 return np0 <= 100*n+99 and np1 > 100*n+99 # _D. S. McNeil_, Feb 21 2011 %o A186394 (PARI) for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==2, print1(n", "))); \\ _Charles R Greathouse IV_, Feb 21 2011 %o A186394 (PARI) N=100; s=0; forprime(p=2, 4e9, if(p>N, if(s==2, print1((N\100)-1, ", ")); s=1; N=100*(p\100+1), s++)) \\ _Charles R Greathouse IV_, Feb 21 2011 %Y A186394 Cf. A038822 (number of primes between 100n and 100n+99), A186311 (first occurrences). %Y A186394 Cf. A181098 (no primes), A186393-A186408 (1 to 16 primes), A186509 (17 primes), A361723 (18 primes). %K A186394 nonn %O A186394 1,1 %A A186394 _Tim Johannes Ohrtmann_, Feb 20 2011