[math-fun] Dan Romik's ambidextrous moving sofa constant

(I'm sure he knows) can be written Out[436]= 1 + Gudermannian[ArcSinh[1]/3] + 4 Sinh[ArcSinh[1]/3]^2 In[437]:= N[%, 22] Out[437]= 1.644955218425440851669 https://www.math.ucdavis.edu/~romik/movingsofa/ billgosper$ ries/ries -l7 1.64495521842544085 Segmentation fault: 11 (Can we ever have enough hardware?) --rwg