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cherry97
Nov 14, 2020

Fun little counting problem i made up

in Math Problems


8 answers0 replies
1
Ian Fowler
Nov 14, 2020

Do 470 , 705 (for example) count as edges?

1
cherry97
Nov 15, 2020

Ian fowler no since they dont share an Edge

1
Ian Fowler
Nov 15, 2020

I'm going to go with 80.

1
cherry97
Nov 15, 2020

Hmmmm... i got 50.

1
Ian Fowler
Nov 16, 2020

Maybe I counted duplicates. Give me a day to re-think it.

1
Ian Fowler
Nov 16, 2020

I'm assuming that the edges are:

123, 369, 9, 0, 7 , 741

and that repeated digits are allowed - 113 and 686 - for example.


3^3 + 3^3 +3^3 - 1 - 1 + 1 = 80

3^3 accounts for the left, top, right edges

-2 as the cubes count 111 and 333 twice

+1 for 000

777 and 999 are counted by the cubes


1
cherry97
Nov 19, 2020

Oops, sry, should’ve been more specific. Repeated digits not allowed.

1
Ian Fowler
Nov 19, 2020

Fair enough. Thanks - Ian