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A098592 Number of primes between n*30 and (n+1)*30. 1
10, 7, 7, 6, 5, 6, 5, 6, 5, 5, 4, 6, 5, 4, 6, 5, 5, 2, 5, 5, 5, 6, 4, 4, 4, 5, 3, 6, 4, 4, 4, 4, 4, 5, 5, 4, 6, 3, 3, 4, 5, 4, 4, 6, 2, 3, 3, 5, 4, 7, 2, 5, 4, 6, 3, 4, 4, 3, 4, 4, 3, 2, 7, 3, 3, 3, 5, 5, 3, 5, 3, 5, 2, 3, 4, 4, 5, 3, 4, 7, 3, 4, 3, 1, 5, 3, 3, 3, 4, 7, 5, 4, 3, 5, 3, 4, 4, 3, 4, 2, 4, 3, 5, 2, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Number of nonzero bits in A098591(n).

The number a(n) is < 8 except for n=0. - Pierre CAMI, Jun 02 2009

Conjecture: if n tends to infinity a(n) may be > 1 and = 2 or 3 or 4 or 5 or 6 or 7. - Pierre CAMI, Jun 02 2009

The probability for a(n) to be > 1 decreases as n increases. - Pierre CAMI, Jun 02 2009

LINKS

Table of n, a(n) for n=0..105.

EXAMPLE

a(1)=7 because there are 7 primes in the interval (30,60): 31,37,41,43,47,53,59. a(26)=3 because the interval of length 30 following 26*30=780 contains 3 primes: 787, 797 and 809.

PROG

See links given in A098591.

CROSSREFS

Cf. A000040 prime numbers, A098591 packed representation of the primes mod 30.

Sequence in context: A246662 A246651 A089245 * A016731 A068444 A210285

Adjacent sequences:  A098589 A098590 A098591 * A098593 A098594 A098595

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Sep 16 2004

EXTENSIONS

Edited by N. J. A. Sloane, Jun 12 2009 at the suggestion of R. J. Mathar

STATUS

approved

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Last modified November 12 16:50 EST 2018. Contains 317116 sequences. (Running on oeis4.)