

A190639


Centuries whose prime pattern repeats in the next century.


11



473267, 726760, 1773439, 1808828, 1919128, 2131583, 2165420, 2339971, 2390652, 2518488, 2802591, 2844914, 2982584, 2996184, 3183263, 3193175, 3250986, 3418185, 3428241, 3633472, 3909324, 3953449, 4280455, 4303819, 4373399, 4658285, 4728653, 4978360, 5165402, 5254365
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OFFSET

1,1


COMMENTS

Alternate definition: Numbers x such that for all N in [100x,100x+99], N is prime iff N+100 is prime.
Contains in particular the first of two consecutive primefree centuries, i.e., N such that there is no prime in [100 N,100 (N+2)], cf. A181098.
x belongs to this sequence if and only if the primality character of (100 * x) + k is the same as (100 * (x+1)) + k for all k = 0..99.  V. Raman, Dec 09 2012


LINKS



FORMULA

a(n) ~ n. In particular there are x  200x/log x + O(x/log^2 x) members of this sequence below x.  Charles R Greathouse IV, Dec 09 2012


EXAMPLE

The first value refers to two consecutive primefree centuries (cf. A181098); the second value is such that 100*a(2)+17 and 100*a(2)+117 are the only primes between 100*a(2) and 100*(a(2)+2). See the link for more examples.


CROSSREFS



KEYWORD

nonn,base


AUTHOR



EXTENSIONS

a(1)a(5) computed by J. K. Andersen, May 15 2011


STATUS

approved



