Wednesday, August 21, 2013

Psi power

The economists among youse certainly know of the gamma function, the analytic construction of the arithmetic factorial function: n Gamma(n) = Gamma(n+1).

How about this function: psi(n) = d/dn ln Gamma(n).

Why is it interesting? (Those of you who have memorized the Chemical Rubber Company Handbook of Mathematical Tables or a similar encyclopedia, please abstain.)


  1. I'll abstain, but here's a hint: if you remember why slide rules work, you're more than half way to the answer.

  2. "The economists among youse..."

    Wabulon, you've learned to talk Brooklyn!


On my tour of Hell...

I saw a man being continually beaten with a carpenter's hammer, blow after merciless blow. "How can this be just?" I asked ...