Rearrange: (1!*2!*3!*4!* ... 100!)/50!
= (1!*2!/1)*(3!*4!/2)*(5!*6!/3))*(7!*8!/4)*......*(97!*98!/49)*(99!*100!/50)
= [(1!)^2 * (3!)^2 * (5!)^2 * (7!)^2 * ...... * (97!)^2 * (99!)^2] * 2^50
This is a product of 51 square numbers.
Edited on September 7, 2017, 9:05 am
blackjack
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flooble's webmaster puzzle
Solution
