Reasoning
Take the numbers in pairs, square the first, and reverse the digits.
1 1 (1 x 1 = 1, reversed is 1)
2 4 (2 x 2 = 4, reversed is 4)
3 9 (3 x 3 = 9, reversed is 9)
4 61 (4 x 4 = 16, reversed is 61)
5 52 (5 x 5 = 25, reversed is 52)
6 63 (6 x 6 = 36, reversed is 63)
7 94 (7 x 7 = 49, reversed is 94)
so we require:
8 46 (8 x 8 = 64, reversed is 46)
?
Puzzle 18
Starting in the bottom left corner and moving either up or right, adding up the numbers along the way, what is the largest sum that can be made?
2
3
6
2
4
2
3
1
5
1
6
1
1
1
7
5
3
5
2
2
3
2
7
2
3
Note: this puzzle is not interactive, and the numbers cannot be clicked.
