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A088968 a(n) = the number of consecutive primes x-3,x+3 such that x=j*(p(n)#/3)/p(k), where 1<=j<p(n+1) and 3<=k<=n and p(k) doesn't divide j. 2
0, 0, 0, 2, 3, 5, 6, 7, 13, 4, 10, 9, 2, 12, 8, 14, 6, 8, 16, 8, 9, 8, 19, 10, 15, 18, 17, 8, 10, 14, 9, 13, 10, 15, 14, 11, 15, 10, 13, 20, 15, 13, 14, 16, 16, 15, 19, 17, 14, 18, 13, 13, 15, 15, 7, 14, 16, 21, 12, 11, 13, 20, 7, 19, 18, 13, 8, 19 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

p(n) is the n-th prime; # denotes primorial (A002110).

a(n) seems to grow like 2 log p(n).

LINKS

Table of n, a(n) for n=1..68.

EXAMPLE

a(5)=3 because for j,k=(1,3),(10,4),(8,5), j*(11#/3)/p(k)+-3 are consecutive primes.

CROSSREFS

Cf. A002110, A087859, A087941.

Sequence in context: A039058 A046158 A070274 * A328451 A057924 A103538

Adjacent sequences:  A088965 A088966 A088967 * A088969 A088970 A088971

KEYWORD

nonn

AUTHOR

Pierre CAMI, Oct 29 2003

EXTENSIONS

Edited by Don Reble, Nov 16 2005

STATUS

approved

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Last modified November 18 19:59 EST 2019. Contains 329288 sequences. (Running on oeis4.)