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A136800
Number of composites in prime gaps of size 3 or larger, in order of appearance.
4
3, 3, 3, 5, 5, 3, 3, 5, 5, 5, 3, 5, 3, 5, 7, 3, 3, 3, 13, 3, 5, 9, 5, 5, 3, 5, 5, 9, 3, 11, 11, 3, 3, 5, 9, 5, 5, 5, 5, 3, 9, 13, 3, 3, 13, 5, 9, 3, 5, 7, 5, 5, 3, 5, 7, 3, 7, 9, 9, 5, 3, 5, 7, 3, 3, 11, 7, 3, 7, 3, 5, 11
OFFSET
1,1
COMMENTS
The sequence counts the terms in the runs of composites associated with A136798-A136799.
A129856 is obtained by removing the composites (9, 15 etc.) from this sequence.
This is sequence A046933, with the zero and all the 1's deleted. - R. J. Mathar, Jan 24 2008
FORMULA
a(n)=A136799(n)-A136798(n)+1.
EXAMPLE
a(1)=3 because in the run 8, 9, 10 there are three terms.
MATHEMATICA
Select[#[[2]]-#[[1]]-1&/@Partition[Prime[Range[100]], 2, 1], #>2&] (* Harvey P. Dale, Apr 08 2015 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Jan 22 2008
EXTENSIONS
Edited by R. J. Mathar, May 27 2009
STATUS
approved