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A098397 Number of primes that are not less than prime(n)-Log2(prime(n)) and not greater than prime(n)+Log2(prime(n)), where Log2=A000523. 2
2, 2, 3, 2, 2, 2, 3, 3, 2, 2, 2, 2, 3, 3, 2, 1, 2, 2, 4, 3, 4, 3, 3, 2, 3, 4, 5, 5, 4, 3, 2, 3, 3, 2, 2, 3, 3, 3, 3, 3, 3, 2, 3, 4, 4, 3, 1, 3, 4, 4, 4, 3, 2, 2, 3, 4, 4, 4, 5, 3, 3, 1, 3, 4, 4, 3, 2, 2, 3, 3, 4, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 3, 3, 4, 3, 3, 4, 4, 4, 3, 2, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 4, 4, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = A000720(A098389(n)) - A000720(A098390(n)-1);

A098398(n) <= A098396(n) <= a(n) <= A097935(n).

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

a(10) = #{p prime: A098389(10) <= p <= A098390(10)} =

= #{p prime: 25 <= p <= 33} = #{29,31} = 2.

CROSSREFS

Sequence in context: A037914 A073813 A104517 * A278744 A082091 A334216

Adjacent sequences:  A098394 A098395 A098396 * A098398 A098399 A098400

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 06 2004

STATUS

approved

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Last modified July 7 23:03 EDT 2020. Contains 335502 sequences. (Running on oeis4.)