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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 14 |
| 4 | 45 |
| 5 | 140 |
| 6 | 438 |
| 7 | 1371 |
| 8 | 4287 |
| 9 | 13413 |
| 10 | 41956 |
| 11 | 131249 |
| 12 | 410572 |
| 13 | 1284352 |
| 14 | 4017713 |
| 15 | 12568213 |
| 16 | 39315905 |
| 17 | 122988066 |
| 18 | 384731445 |
| 19 | 1203517448 |
| 20 | 3764844982 |
| 21 | 11777193395 |
| 22 | 36841433019 |
| 23 | 115247422841 |
| 24 | 360517151000 |
| 25 | 1127770261265 |
| 26 | 3527892525112 |
| 27 | 11035958382864 |
[1,1,5,14,45,140,438,1371,4287,13413,41956,131249, 410572,1284352,4017713,12568213,39315905, 122988066,384731445,1203517448,3764844982, 11777193395,36841433019,115247422841,360517151000, 1127770261265,3527892525112,11035958382864] |