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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 96 |
| 7 | 308 |
| 8 | 1052 |
| 9 | 3648 |
| 10 | 13003 |
| 11 | 47006 |
| 12 | 172605 |
| 13 | 640662 |
| 14 | 2402388 |
| 15 | 9082538 |
| 16 | 34590673 |
| 17 | 132566826 |
| 18 | 510904724 |
| 19 | 1978728356 |
| 20 | 7697565819 |
| 21 | 30063818314 |
| 22 | 117840547815 |
| 23 | 463405921002 |
| 24 | 1827768388175 |
| 25 | 7228779397588 |
| 26 | 28661434308095 |
| 27 | 113903170011006 |
| 28 | 453632267633931 |
[1,2,4,11,30,96,308,1052,3648,13003,47006,172605, 640662,2402388,9082538,34590673,132566826, 510904724,1978728356,7697565819,30063818314, 117840547815,463405921002,1827768388175, 7228779397588,28661434308095,113903170011006, 453632267633931] |