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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 16 |
| 5 | 35 |
| 6 | 97 |
| 7 | 234 |
| 8 | 626 |
| 9 | 1603 |
| 10 | 4218 |
| 11 | 10947 |
| 12 | 28767 |
| 13 | 75026 |
| 14 | 196654 |
| 15 | 514269 |
| 16 | 1346895 |
| 17 | 3524579 |
| 18 | 9229159 |
| 19 | 24157818 |
| 20 | 63250217 |
| 21 | 165580380 |
| 22 | 433505386 |
| 23 | 1134903171 |
| 24 | 2971244450 |
| 25 | 7778742084 |
| 26 | 20365086102 |
| 27 | 53316292776 |
| 28 | 139584059112 |
| 29 | 365435296163 |
| 30 | 956722544582 |
[1,3,6,16,35,97,234,626,1603,4218,10947,28767, 75026,196654,514269,1346895,3524579,9229159, 24157818,63250217,165580380,433505386,1134903171, 2971244450,7778742084,20365086102,53316292776, 139584059112,365435296163,956722544582] |