(-1)k⁢ζ(k)⁡(-2⁢n)=2⁢(-1)n(2⁢π)2⁢n+1⁢∑m=0k∑r=0m(km)⁢(mr)⁢ℑ⁡(ck-m)⁢Γ(r)⁡(2⁢n+1)⁢ζ(m-r)⁡(2⁢n+1),