A186402 Numbers k such that there are 10 primes between 100*k and 100*k + 99.

21, 24, 31, 52, 53, 57, 66, 71, 77, 78, 79, 81, 102, 104, 108, 109, 110, 112, 113, 127, 133, 140, 146, 159, 175, 177, 180, 185, 197, 198, 205, 214, 232, 244, 254, 257, 263, 264, 266, 269, 270, 272, 274, 287, 292, 295, 298

Offset: 1

Author

Tim Johannes Ohrtmann, Feb 20 2011

Keywords

• nonn

Comments

There are 18634704 possible prime patterns for centuries having 10 primes. - Tim Johannes Ohrtmann, Aug 27 2015

Examples

			21 is in this sequence because there are 10 primes between 2100 and 2199 (2111, 2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161 and 2179).
		

Links

• T. D. Noe, Table of n, a(n) for n = 1..1000

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).

Programs

Mathematica

Select[Range[300], PrimePi[100 # + 99] - PrimePi[100 #]==10 &] (* Vincenzo Librandi, Feb 13 2015 *)

PARI

for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==10, print1(n", "))); \\ Charles R Greathouse IV, Feb 21 2011

PARI

N=100; s=0; forprime(p=2, 4e9, if(p>N, if(s==10, print1((N\100)-1, ", ")); s=1; N=100*(p\100+1), s++)) \\ Charles R Greathouse IV, Feb 21 2011