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A181098
Primefree centuries (i.e., numbers k such that no prime exists between 100*k and 100*k+99).
27
16718, 26378, 31173, 39336, 46406, 46524, 51782, 55187, 58374, 58452, 60129, 60850, 63338, 63762, 67898, 69587, 71299, 75652, 78035, 78269, 80277, 83674, 84213, 89052, 95490, 97080, 100881, 101527, 103438, 105916, 111772, 112967
OFFSET
1,1
COMMENTS
The first consecutive terms are 473267, 473268; see A190639. - M. F. Hasler, May 15 2011
FORMULA
a(n) = n + 100n/log n - O(n/log^2 n). - Charles R Greathouse IV, Sep 08 2017
EXAMPLE
16718 is a term because there is no prime between 1671800 and 1671899.
MATHEMATICA
Flatten[Position[Differences[PrimePi[100*Range[0, 113000]]], 0]]-1 (* Harvey P. Dale, Dec 18 2021 *)
PROG
(PARI) is(n)=nextprime(100*n)>100*n+99 \\ Charles R Greathouse IV, Apr 28 2015
CROSSREFS
Cf. A038822 (number of primes between 100n and 100n+99), A186311 (first occurrences).
Cf. A186393-A186408 (1 to 16 primes), A186509 (17 primes), A361723 (18 primes).
Sequence in context: A345829 A224572 A186311 * A365813 A202896 A183727
KEYWORD
nonn
AUTHOR
Jeff Burch, Oct 02 2010
STATUS
approved