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A081247 Number of numbers k<=n with mu(k+n)=mu(k), where mu=A008683 (Moebius function). 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
Cf. A081248.
Sequence in context: A193535 A332645 A344855 * A298753 A173050 A172380
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 12 2003
STATUS
approved

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Last modified July 22 10:46 EDT 2024. Contains 374490 sequences. (Running on oeis4.)