|
|
A261869
|
|
First differences of A055615.
|
|
4
|
|
|
-3, -1, 3, -5, 11, -13, 7, 0, 10, -21, 11, -13, 27, 1, -15, -17, 17, -19, 19, 21, 1, -45, 23, 0, 26, -26, 0, -29, -1, -1, 31, 33, 1, 1, -35, -37, 75, 1, -39, -41, -1, -1, 43, 0, 46, -93, 47, 0, 0, 51, -51, -53, 53, 55, -55, 57, 1, -117, 59, -61, 123, -62, 0
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
a(n) = (n+1)*mu(n+1) - n*mu(n), where mu = A008683 (Moebius function);
abs(a(n)) <= 2*n + 1.
|
|
LINKS
|
|
|
MATHEMATICA
|
#[[2]]-#[[1]]&/@Partition[Table[n*MoebiusMu[n], {n, 70}], 2, 1] (* Harvey P. Dale, Apr 17 2016 *)
|
|
PROG
|
(Haskell)
import Data.List (genericIndex)
a261869 n = genericIndex a261869_list (n - 1)
a261869_list = zipWith (-) (tail a055615_list) a055615_list
|
|
CROSSREFS
|
|
|
KEYWORD
|
sign
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|