Comment on What are the most mindblowing fact in mathematics?

• emax_gomax@lemmy.world ⁨2⁩ ⁨years⁩ ago

  Yep. N * (n + 1) / 2.

  You can think of it as.

     1     + 2   +  3  + 4    ... 100
  + 100 + 99 + 98 + 97  +  1
  

  101 + 101 + 101 ... 101
  = 2 * sum(1+2+3...100)
  

  source