Counting Polydivisible Numbers
We can find the actual values of F(n) by counting the number of polydivisible numbers with a given length :
| Length n | F(n) | Estimate of F(n) | Length n | F(n) | Estimate of F(n) | Length n | F(n) | Estimate of F(n) | ||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 9 | 9 | 11 | 2225 | 2255 | 21 | 18 | 17 | ||
| 2 | 45 | 45 | 12 | 2041 | 1879 | 22 | 12 | 8 | ||
| 3 | 150 | 150 | 13 | 1575 | 1445 | 23 | 6 | 3 | ||
| 4 | 375 | 375 | 14 | 1132 | 1032 | 24 | 3 | 1 | ||
| 5 | 750 | 750 | 15 | 770 | 688 | 25 | 1 | 1 | ||
| 6 | 1200 | 1250 | 16 | 571 | 430 | |||||
| 7 | 1713 | 1786 | 17 | 335 | 253 | |||||
| 8 | 2227 | 2232 | 18 | 180 | 141 | |||||
| 9 | 2492 | 2480 | 19 | 90 | 74 | |||||
| 10 | 2492 | 2480 | 20 | 44 | 37 |
There are 20,456 polydivisible numbers altogether, and the longest polydivisible number, which has 25 digits, is :
- 360 852 885 036 840 078 603 672 5
Read more about this topic: Polydivisible Number
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