Submitted by Bill Gosper, August 1996, .3725074107813666344619918665801191335356894977716540515556574352422001 20636201854384926 as explained by himself, An Inverse Symbolic Calculator candidate... r :~ .372507410781366634461991866580119133535689497771654051555657435242200120636201854384926 = real root of Ei(x) = (c2081) ('integrate(%e^t/t,t,-inf,x),(%%=apply_nouns(%%))=exp_int(x)); x / t [ %e (d2081) --- --- dt = - Gamma(0, - x) = exp_int(x) ] t / - inf so we can integrate from r instead of from -oo, (c2082) exp_int(x)='integrate(%e^t/t,t,r,x); x / t [ %e (d2082) exp_int(x) = I --- dt, ] t / r avoiding the pole at 0 when x>0. (Is r already known in other terms??) Bill Gosper # This is the electronic signature for Plouffe's Inverter # # Ceci est la signature électronique pour l'Inverseur de Plouffe # # Copyright : Simon Plouffe/Plouffe's Inverter (c) 1986. # # http://www.lacim.uqam.ca/pi #