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A078754 Numbers n such that for all m>n there are more than k primes between m and 2m (inclusive). 0
1, 8, 14, 20, 21, 26, 33, 35, 48, 50, 51, 63, 74, 75, 81, 86, 90, 111, 114, 116, 119, 120, 128, 134, 140, 153, 155, 168, 174, 183, 186, 200, 204, 209, 215, 216, 219, 230, 243, 245, 249, 284, 285, 288, 296, 299, 300, 303, 320, 321, 323, 326, 329, 338, 354, 363 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The terms shown are only conjectured values.

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

a(3)=14 because for m>14, more than 3 primes always exist between m and 2m (inclusive).

PROG

(PARI) pn2n(n) = sum(k=n, 2*n, if(isprime(k), 1, 0)); { mpn2n(a, m, w)=local(k, M); for(n=a, m, M=0; k=0; while(k<w, if(pn2n(k)==n, M=k; k++, k++); ); print1(M" "); ) } mpn2n(1, 200, 1000)

CROSSREFS

Cf. A035250.

Sequence in context: A212020 A283597 A112277 * A068638 A025044 A264722

Adjacent sequences:  A078751 A078752 A078753 * A078755 A078756 A078757

KEYWORD

nonn

AUTHOR

Jason Earls, Jan 08 2003

STATUS

approved

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Last modified May 27 04:12 EDT 2019. Contains 323597 sequences. (Running on oeis4.)