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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 25 |
| 2 | 235 |
| 3 | 1330 |
| 4 | 5488 |
| 5 | 18228 |
| 6 | 51660 |
| 7 | 129690 |
| 8 | 295845 |
| 9 | 624481 |
| 10 | 1236235 |
| 11 | 2318680 |
| 12 | 4153240 |
| 13 | 7149520 |
| 14 | 11888304 |
| 15 | 19174572 |
| 16 | 30101985 |
| 17 | 46130385 |
| 18 | 69177955 |
| 19 | 101729782 |
| 20 | 146964664 |
| 21 | 208902100 |
| 22 | 292571500 |
| 23 | 404205750 |
| 24 | 551461365 |
| 25 | 743667561 |
| 26 | 992106675 |
[1,25,235,1330,5488,18228,51660,129690,295845, 624481,1236235,2318680,4153240,7149520,11888304, 19174572,30101985,46130385,69177955,101729782, 146964664,208902100,292571500,404205750,551461365, 743667561,992106675] |