I fixed the problem which you encountered of Lambda[14,7] not converging, see the new notebook. I think that the integral is only convergent for t=nt0 where n is an integer. However, taking into account this assumption does not have any effect. I also tried to look at the answers for tau0=1 and tau=1,2,3,4,5 to see if I can figure out the analytical function since I get analytical results back, but i don't see it yet.
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