a(n) = Sum_{k=1..n} (-n)^(floor(n/k) - 1).
A345036
a(n) = Sum_{k=1..n} (-n)^(floor(n/k) - 1).
Terms
- a(0) =1a(1) =-1a(2) =11a(3) =-66a(4) =623a(5) =-7743a(6) =117695a(7) =-2097676a(8) =43046069a(9) =-999989915a(10) =25937439347a(11) =-743008621122
External references
- oeis: A345036