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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 13 |
| 5 | 37 |
| 6 | 78 |
| 7 | 218 |
| 8 | 457 |
| 9 | 1273 |
| 10 | 2666 |
| 11 | 7422 |
| 12 | 15541 |
| 13 | 43261 |
| 14 | 90582 |
| 15 | 252146 |
| 16 | 527953 |
| 17 | 1469617 |
| 18 | 3077138 |
| 19 | 8565558 |
| 20 | 17934877 |
| 21 | 49923733 |
| 22 | 104532126 |
| 23 | 290976842 |
| 24 | 609257881 |
| 25 | 1695937321 |
| 26 | 3551015162 |
| 27 | 9884647086 |
| 28 | 20696833093 |
| 29 | 57611945197 |
| 30 | 120629983398 |
| 31 | 335787024098 |
[1,2,6,13,37,78,218,457,1273,2666,7422,15541, 43261,90582,252146,527953,1469617,3077138,8565558, 17934877,49923733,104532126,290976842,609257881, 1695937321,3551015162,9884647086,20696833093, 57611945197,120629983398,335787024098] |