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Triangular number AND sum of first m factorials
01-11-2018, 10:30 PM
Post: #14
John Keith Offline
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RE: Triangular number AND sum of first m factorials
(01-11-2018 10:21 AM)Paul Dale Wrote:  Thanks Smile Don't let my proof stop your hunt, you'll be able to wile away many hours looking...

I hadn't realised that all square numbers that end in '5' actually end in '25'. I must have seen this before but never noticed or remembered it.


Pauli

I figured it was hopeless since I tested all sums of factorials up to 1000 (over 2500 digits) with no triangle numbers found. Took almost 20 min. on the emulator.

An interesting and educational thread indeed!

John
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RE: Triangular number AND sum of first m factorials - John Keith - 01-11-2018 10:30 PM



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