OFFSET
1,1
COMMENTS
a(k) = 0 for k in A026424. - David A. Corneth, May 23 2021
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..20000
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
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 23 2021
STATUS
approved