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A186396
Numbers k such that there are 4 primes between 100*k and 100*k + 99.
1
314, 356, 524, 662, 831, 881, 1037, 1101, 1124, 1307, 1370, 1433, 1623, 1713, 1733, 1755, 1801, 1808, 1831, 1880, 1956, 2031, 2150, 2178, 2202, 2222, 2231, 2330, 2374, 2502, 2503, 2532, 2545, 2611, 2618, 2656, 2659, 2665
OFFSET
1,1
COMMENTS
There are 47878 possible prime patterns for centuries having 4 primes. - Tim Johannes Ohrtmann, Aug 27 2015
EXAMPLE
314 is in this sequence because there are 4 primes between 31400 and 31499 (31469, 31477, 31481 and 31489).
PROG
(PARI) for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==4, print1(n", "))); \\ Charles R Greathouse IV, Feb 21 2011
(PARI) N=100; s=0; forprime(p=2, 1e6, if(p>N, if(s==4, 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-A186408 (1 to 16 primes), A186509 (17 primes), A361723 (18 primes).
Sequence in context: A025352 A025344 A219962 * A107117 A161963 A276993
KEYWORD
nonn
AUTHOR
STATUS
approved