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Monday, March 25, 2013

Start-of-the-Week



Sol Lederman's latest podcast is with the interesting mother-daughter team who co-wrote "Math On Trial," which takes a critical look at the (ab)use of math/statistics in courtroom proceedings:

http://wildaboutmath.com/2013/03/24/leila-schneps-coralie-colmez-inspired-by-math-26/

My own latest interview is with writer-extraordinaire Clifford Pickover here:

http://mathtango.blogspot.com/2013/03/clifford-pickover-one-man-carnival.html

(I still have a list of folks to possibly contact for interviews, but again, if any readers have suggestions they'd like to send along via comments or email, let me know.)

And to get your thinking caps revved up on a Monday morning here's a simple puzzle I've taken directly from Futility Closet a bit ago:

The digits 123456789 can be arranged to form 362,880 distinct 9-digit numbers. How many of these are prime?
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ANSWER:  
since the sum of those 9 digits is 45, no matter how they are rearranged, any resulting number will be divisible by 9. Thus, NONE are primes.








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