Following on from DAY 240, here’s another one of the unique Keith Number challenges made famous by Mike Keith and similar to Fibonacci numbers. If you like playing around with numbers, you’ll love having a go at this fun concept.
The first 2-digit Keith Number, 14, is worked out by following a pattern:
- 1+4=5; 4+5=9; 5+9=14 (the total arrives back to the original number).
The second 2-digit Keith Number, 19, is worked out in a similar way:
- 1+9=10; 9+10=19 (the total again arrives back to the original number).
By following this pattern, the third and fourth 2-digit Keith Numbers are 28 and 47. There are only two more below 100, what are they?
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid of 49 different numbers, ranging from 2 up to 84.
The 2nd & 3rd rows contain the following fourteen numbers:
8 13 17 25 28 36 42 45 48 55 63 64 66 80
What is the sum of the square numbers?
. . . can be found when clicking this.