Once again, my solution is free from Mathematica and other online programming
solutions, although again I accepted my husband’s list of possible solutions to a 10-
long 2-digit prime raised to a prime – there were 8 of these.
It was easy to find the consistently-thrown number: 5. Other numbers gave the
wrong number of cells; only 5 gave 10 of them. . I highlighted the 10 cells that were
landed on in my rough copy, so that I could easily check they were mutually
exclusive.
Once I had the 8 prime^prime solutions the gridfill was very straightforward, although
it would have been a lot easier if my simple calculators had had a display longer than
8 digits. So some hand-multiplication was involved, but not much.
The check at 42dn was a nice touch.
I’d love to see another snakes-and-ladders-themed numerical – perhaps with some
sort of revelation or message at the end to spice it up.
My method for solving Snakes and Ladders, if anyone’s interested, is shown at
Appendix A.
Best wishes,
Gill Cocks
Appendix A to L4895 solution: the gridfill (at least, the first 11 steps)
1. Choose a solution (from the 8 possibles) for 61ac that also satisfies the 2
possibilities for 61dn
1804229351 / 1296
2. There is only one solution for 60ac
2073071593
3. Cell1 must be 9, and cell 20 must be 1
4. Cell 46 is 2/8, cell 30 is 0/2/4/8 and cell 85 is 1/5/9
5. Therefore 81ac is
1350125107
6. Only one solution fits 40ac
6321363049
7. 68dn can now be derived
3570
8. Cells 11 & 41 are 2 and 9
9. 2 possibilities for 21 ac, and these give 15 up
1568
10. 100ac is
2357947691
11. 20ac is
1287913472
12. At this point I looked at the ups and downs, and the whole grid dropped
As a lover of Maths, I found this easier than quite a few of the recent Listener maths puzzles. Ta IOA and Chalicea.