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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 5 |
| 3 | 10 |
| 4 | 31 |
| 5 | 90 |
| 6 | 259 |
| 7 | 746 |
| 8 | 2150 |
| 9 | 6192 |
| 10 | 17831 |
| 11 | 51346 |
| 12 | 147850 |
| 13 | 425724 |
| 14 | 1225834 |
| 15 | 3529664 |
| 16 | 10163285 |
| 17 | 29264046 |
| 18 | 84262511 |
| 19 | 242624302 |
| 20 | 698608939 |
| 21 | 2011564422 |
| 22 | 5792069134 |
| 23 | 16677598712 |
| 24 | 48021232079 |
| 25 | 138271627638 |
| 26 | 398137284986 |
[0,5,10,31,90,259,746,2150,6192,17831,51346, 147850,425724,1225834,3529664,10163285,29264046, 84262511,242624302,698608939,2011564422, 5792069134,16677598712,48021232079,138271627638, 398137284986] |