No 22
153
So what's amazing about 153 ?
Try the following sum:
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17
Not only that...
Try the following sum:
1! + 2! + 3! + 4! + 5!
( ! is the
factorial
sign )
And if that's not enough:
Try the following sum:
1
3
+ 5
3
+ 3
3
This last fact is shared by very few other numbers.
They are called the three digit
Armstrong Numbers
and there are only four of them.
In increasing order they are: 153, ***, 371 and 407.
Can you find the missing one?
If you have answers, discoveries, new questions etc to do with this Number Fact then...
E-mail us at
madrascollege.maths@fife.gov.uk
...and we will publish them here.
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