|
|
A210700
|
|
A047160(3n): smallest m >= 0 with both 3n - m and 3n + m prime.
|
|
3
|
|
|
0, 1, 2, 1, 2, 1, 2, 5, 4, 1, 4, 5, 2, 1, 2, 5, 8, 7, 4, 1, 4, 5, 2, 1, 4, 5, 2, 5, 14, 7, 4, 7, 2, 1, 2, 1, 2, 13, 10, 7, 14, 13, 2, 5, 4, 1, 10, 5, 10, 1, 4, 7, 8, 5, 2, 5, 8, 7, 4, 1, 10, 5, 8, 1, 2, 1, 10, 7, 16, 13, 14, 17, 8, 11, 2, 1, 2, 5, 4, 1, 14, 5
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,3
|
|
COMMENTS
|
This sequence is interesting because, apart from a(2)=1, A155764 appears to consist only of multiples of three. Equivalently, since n and A047160(n) are coprime (for nonzero A047160(n)), no multiple of three appears to occur in A155765.
|
|
LINKS
|
|
|
MATHEMATICA
|
sml[n_]:=Module[{m=0}, While[!PrimeQ[3n-m]||!PrimeQ[3n+m], m++]; m]; Array[ sml, 100] (* Harvey P. Dale, Sep 23 2022 *)
|
|
CROSSREFS
|
Cf. A210701 (location of records in this sequence), A210702 (records in this sequence).
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|