C=limn→∞⁡(∑k=1nk⁢ln⁡k-(12⁢n2+12⁢n+112)⁢ln⁡n+14⁢n2)=γ+ln⁡(2⁢π)12-ζ′⁡(2)2⁢π2=112-ζ′⁡(-1),