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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 11 |
| 5 | 23 |
| 6 | 60 |
| 7 | 182 |
| 8 | 589 |
| 9 | 1960 |
| 10 | 6641 |
| 11 | 22849 |
| 12 | 79676 |
| 13 | 281048 |
| 14 | 1001100 |
| 15 | 3595865 |
| 16 | 13009663 |
| 17 | 47366234 |
| 18 | 173415160 |
| 19 | 638044198 |
| 20 | 2357941155 |
| 21 | 8748646416 |
| 22 | 32576869239 |
| 23 | 121701491725 |
| 24 | 456012458960 |
| 25 | 1713339737046 |
| 26 | 6453584646774 |
| 27 | 24364925259967 |
| 28 | 92185136438926 |
| 29 | 349479503542513 |
[0,1,3,6,11,23,60,182,589,1960,6641,22849,79676, 281048,1001100,3595865,13009663,47366234, 173415160,638044198,2357941155,8748646416, 32576869239,121701491725,456012458960, 1713339737046,6453584646774,24364925259967, 92185136438926,349479503542513] |