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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 25 |
| 7 | 67 |
| 8 | 184 |
| 9 | 519 |
| 10 | 1489 |
| 11 | 4342 |
| 12 | 12812 |
| 13 | 38207 |
| 14 | 114934 |
| 15 | 348397 |
| 16 | 1063050 |
| 17 | 3262588 |
| 18 | 10064645 |
| 19 | 31190985 |
| 20 | 97061431 |
| 21 | 303165207 |
| 22 | 950115502 |
| 23 | 2986817742 |
| 24 | 9415920424 |
| 25 | 29760442192 |
| 26 | 94286758293 |
| 27 | 299377379027 |
| 28 | 952521579944 |
| 29 | 3036380284111 |
| 30 | 9696325863803 |
[1,1,2,4,10,25,67,184,519,1489,4342,12812,38207, 114934,348397,1063050,3262588,10064645,31190985, 97061431,303165207,950115502,2986817742, 9415920424,29760442192,94286758293,299377379027, 952521579944,3036380284111,9696325863803] |