The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 20 |
| 4 | 83 |
| 5 | 262 |
| 6 | 777 |
| 7 | 2117 |
| 8 | 5278 |
| 9 | 12353 |
| 10 | 27893 |
| 11 | 58831 |
| 12 | 118985 |
| 13 | 235504 |
| 14 | 443653 |
| 15 | 810431 |
| 16 | 1459822 |
| 17 | 2529977 |
| 18 | 4285656 |
| 19 | 7192569 |
| 20 | 11698167 |
| 21 | 18689016 |
| 22 | 29678739 |
| 23 | 45907880 |
| 24 | 70000817 |
| 25 | 106315189 |
| 26 | 157902365 |
| 27 | 231761845 |
| 28 | 339336920 |
| 29 | 487306673 |
[1,5,20,83,262,777,2117,5278,12353,27893,58831, 118985,235504,443653,810431,1459822,2529977, 4285656,7192569,11698167,18689016,29678739, 45907880,70000817,106315189,157902365,231761845, 339336920,487306673] |