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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 49 |
| 5 | 157 |
| 6 | 669 |
| 7 | 2359 |
| 8 | 10469 |
| 9 | 38031 |
| 10 | 171947 |
| 11 | 654365 |
| 12 | 2963317 |
| 13 | 11615139 |
| 14 | 53048663 |
| 15 | 211305971 |
| 16 | 971575373 |
| 17 | 3937700723 |
| 18 | 18158329543 |
| 19 | 74598316371 |
| 20 | 345340823051 |
| 21 | 1432498112841 |
| 22 | 6653892360649 |
| 23 | 27858328150673 |
| 24 | 129689043036749 |
| 25 | 547253347884923 |
| 26 | 2553540861061331 |
| 27 | 10843856927588551 |
[1,1,5,11,49,157,669,2359,10469,38031,171947, 654365,2963317,11615139,53048663,211305971, 971575373,3937700723,18158329543,74598316371, 345340823051,1432498112841,6653892360649, 27858328150673,129689043036749,547253347884923, 2553540861061331,10843856927588551] |