From: Solving Robin problems in multiply connected regions via an integral equation with the generalized Neumann kernel
n
\(\boldsymbol {\|u(\eta(t))-u_{n}(\eta(t))\|_{\infty}}\)
32
\(1.56~(-2)\)
64
\(8.57~(-4)\)
128
\(5.16~(-5)\)
256
\(3.21~(-6)\)
512
\(1.99~(-7)\)
1,024
\(1.24~(-8)\)