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+--- Thread: Bug: Attempting to calculate a double sum crashes the CAS (/thread-5292.html)
Bug: Attempting to calculate a double sum crashes the CAS - quinyu - 12-07-2015 10:06 PM
Calculating the following double sum causes a calculator crash:
[attachment=2931]
While I understand that the closed form is nasty (involves the Psi function, plus the Euler-Mascheroni constant), the Prime could just say "no idea" instead of crashing. (Solution from Wolfram Alpha. TI nSpire CAS just returns the expression.)
[attachment=2932]
This is Software Version 2015 6 17 (8151), HW ver C, CAS version 1.1.2-11, OS 0.037.526
RE: Bug: Attempting to calculate a double sum crashes the CAS - quinyu - 12-07-2015 10:42 PM
HP 50g delivers a half-solution, giving
[attachment=2933]
RE: Bug: Attempting to calculate a double sum crashes the CAS - DrD - 12-07-2015 10:54 PM
Does this work on Wolfram, Matlab, et al?
RE: Bug: Attempting to calculate a double sum crashes the CAS - quinyu - 12-07-2015 11:42 PM
Wolfram Alpha gives identical result. (Sorry, earlier I thought that Mathematica would too - no, see below.) Maple 18 gives:
[attachment=2934] (some little editing to keep style consistent, and factor things a little)
MuPAD gives the same half-solution as the HP 50g. Matlab R2015a also.
RE: Bug: Attempting to calculate a double sum crashes the CAS - quinyu - 12-08-2015 07:41 AM
Best sum that I could find with Mathematica 10.0 is:
[attachment=2935], where H_n is the nth harmonic number. This is the one I like the most, so far.