Search: a081248 -id:a081248
|
|
A081247
|
|
Number of numbers k<=n with mu(k+n)=mu(k), where mu=A008683 (Moebius function).
|
|
+10
1
|
|
|
0, 0, 1, 2, 3, 1, 0, 5, 4, 3, 3, 7, 2, 4, 4, 10, 3, 6, 5, 12, 4, 3, 6, 16, 9, 6, 7, 13, 10, 10, 7, 16, 6, 9, 8, 25, 9, 9, 10, 22, 13, 13, 12, 19, 10, 9, 16, 29, 10, 16, 14, 24, 10, 21, 17, 31, 9, 13, 20, 37, 16, 14, 18, 30, 18, 20, 21, 35, 13, 16, 27, 49, 21, 15, 13, 42, 22, 25, 19, 39, 26
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,4
|
|
LINKS
|
|
|
EXAMPLE
|
n=10: mu(3+10)=mu(3)=-1, mu(7+10)=mu(7)=-1, mu(8+10)=mu(8)=0 and mu(k+10)<>mu(k) for k in {1,2,4,5,6,8,9}, therefore a(10)=3.
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
Search completed in 0.005 seconds
|