13 Apr
2011
13 Apr
'11
6:11 p.m.
Via the fixpoint combinator: X = Y(EC) = EC(Y(EC)) On Wed, Apr 13, 2011 at 12:59 PM, Dan Asimov <dasimov@earthlink.net> wrote:
PUZZLE: Let EC(X) denote the Euler characteristic of X.
Solve for X:
EC(X) = X
--Dan
P.S. Thanks to Evan O'Dorney for pointing out a case I had overlooked.
Sometimes the brain has a mind of its own.
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