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A186394 Numbers n such that there are 2 primes between 100*n and 100*n + 99. 2
3020, 3709, 4484, 4617, 4806, 4921, 5072, 5423, 5616, 6041, 6194, 6231, 6452, 6485, 6683, 6828, 7101, 7365, 7454, 7532, 7839, 8096, 8157, 8728, 8738, 9221, 9486, 9635, 9796, 10152, 10506, 10720, 10852, 11261, 11621, 11736, 11953, 11992 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are 780 possible prime patterns for centuries having 2 primes. - Tim Johannes Ohrtmann, Aug 27 2015

LINKS

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

EXAMPLE

3020 is in this sequence because there are 2 primes between 302000 and 302099 (302009 and 302053).

PROG

(Sage)

def is_A186394(n):

    np0 = next_prime(next_prime(100*n))

    np1 = next_prime(np0)

    return np0 <= 100*n+99 and np1 > 100*n+99  # D. S. McNeil, Feb 21 2011

(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

(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

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).

Sequence in context: A086746 A031816 A252381 * A236200 A252620 A104960

Adjacent sequences:  A186391 A186392 A186393 * A186395 A186396 A186397

KEYWORD

nonn

AUTHOR

Tim Johannes Ohrtmann, Feb 20 2011

STATUS

approved

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Last modified March 4 05:42 EST 2021. Contains 341779 sequences. (Running on oeis4.)