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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 6 |
| 5 | 11 |
| 6 | 15 |
| 7 | 22 |
| 8 | 40 |
| 9 | 72 |
| 10 | 118 |
| 11 | 199 |
| 12 | 355 |
| 13 | 604 |
| 14 | 920 |
| 15 | 1306 |
| 16 | 1906 |
| 17 | 3281 |
| 18 | 6985 |
| 19 | 16446 |
| 20 | 38034 |
| 21 | 82490 |
| 22 | 168076 |
| 23 | 325935 |
| 24 | 604213 |
| 25 | 1068941 |
| 26 | 1815745 |
| 27 | 3038319 |
| 28 | 5246725 |
| 29 | 9796132 |
| 30 | 19966752 |
| 31 | 42918987 |
| 32 | 92984247 |
| 33 | 197027405 |
| 34 | 402932711 |
| 35 | 792381923 |
| 36 | 1499918753 |
| 37 | 2746078246 |
[0,1,4,6,11,15,22,40,72,118,199,355,604,920,1306, 1906,3281,6985,16446,38034,82490,168076,325935, 604213,1068941,1815745,3038319,5246725,9796132, 19966752,42918987,92984247,197027405,402932711, 792381923,1499918753,2746078246] |