|
|
A068015
|
|
Gaps between non-twin primes.
|
|
1
|
|
|
21, 14, 10, 6, 14, 12, 4, 6, 8, 16, 14, 4, 26, 6, 4, 6, 38, 12, 10, 18, 6, 6, 14, 16, 14, 10, 14, 6, 16, 6, 8, 6, 6, 4, 6, 8, 4, 8, 30, 4, 6, 8, 10, 12, 8, 4, 8, 4, 6, 32, 6, 10, 6, 14, 10, 6, 14, 6, 18, 16, 6, 20, 4, 6, 8, 10, 8, 10
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
The first primes that are not 2 less than or 2 greater than another prime are 2, 23, 37,... (A007510). The second gap is 37-23=14, so a(2)=14.
|
|
MATHEMATICA
|
ntpg[n_]:=Module[{prn=Prime[Range[n]], tp}, tp=Union[Flatten[Select[ Partition[prn, 2, 1], Last[#]- First[#] ==2&]]]; Differences[Complement[ prn, tp]]]; ntpg[200] (* Harvey P. Dale, Apr 09 2012 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|