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A186407
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Numbers k such that there are 15 primes between 100*k and 100*k + 99.
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2
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8, 12, 16, 22, 23, 26, 33, 40, 49, 63, 75, 94, 375, 424, 1131, 1572, 3442, 3922, 7393, 9780, 13939, 16528, 17492, 29673, 71338, 75877, 237421, 464977, 514483, 687352, 747574, 981953, 1040840, 1269778, 1298137, 1346413, 1790287, 1884223, 2330647, 2527249, 2601874, 2813749
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OFFSET
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1,1
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COMMENTS
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There are 12815608 possible prime patterns for centuries having 15 primes. - Tim Johannes Ohrtmann, Aug 27 2015
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LINKS
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EXAMPLE
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8 is in this sequence because there are 15 primes between 800 and 899 (809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883 and 887).
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PROG
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(PARI) for(n=1, 1e6, if(sum(k=100*n, 100*(n+1), ispseudoprime(k))==15, print1(n", "))); \\ Charles R Greathouse IV, Feb 21 2011
(PARI) N=100; s=0; forprime(p=2, 4e9, if(p>N, if(s==15, print1((N\100)-1, ", ")); s=1; N=100*(p\100+1), s++)) \\ Charles R Greathouse IV, Feb 21 2011
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CROSSREFS
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Cf. A038822 (number of primes between 100n and 100n+99), A186311 (first occurrences).
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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