|
|
|
|
2, 0, 0, 6, 0, 4, 0, 0, 14, 8, 0, 0, 0, 12, 16, 22, 0, 0, 0, 0, 24, 20, 0, 20, 42, 24, 0, 0, 0, 0, 0, 0, 40, 32, 48, 42, 0, 36, 48, 40, 0, 0, 0, 0, 0, 44, 0, 0, 86, 0, 64, 0, 0, 40, 80, 60, 72, 56, 0, 48, 0, 60, 0, 86, 96, 0, 0, 0, 88, 0, 0, 0, 0, 72, 0, 0, 120, 0, 0, 0, 122, 80, 0, 72, 128, 84, 112, 100, 0, 56, 144
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
|
|
MATHEMATICA
|
With[{nn = 91}, Map[# + Abs[#] &, Drop[CoefficientList[Series[Sum[LiouvilleLambda[k] k x^k/(1 - x^k), {k, 1, #}], {x, 0, #}], x], 1] &[nn]]] (* Michael De Vlieger, May 24 2021, after Jean-François Alcover at A061020 *)
|
|
PROG
|
(PARI)
A061020(n) = {my(f=factorint(n)); prod(k=1, #f[, 2], ((-f[k, 1])^(f[k, 2]+1)-1)/(-f[k, 1]-1))};
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|