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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 13 |
| 6 | 35 |
| 7 | 97 |
| 8 | 271 |
| 9 | 761 |
| 10 | 2143 |
| 11 | 6042 |
| 12 | 17043 |
| 13 | 48081 |
| 14 | 135656 |
| 15 | 382752 |
| 16 | 1079939 |
| 17 | 3047074 |
| 18 | 8597406 |
| 19 | 24257838 |
| 20 | 68444231 |
| 21 | 193117503 |
| 22 | 544886995 |
| 23 | 1537415492 |
| 24 | 4337865331 |
| 25 | 12239421132 |
| 26 | 34533905116 |
| 27 | 97438480950 |
[1,1,2,5,13,35,97,271,761,2143,6042,17043,48081, 135656,382752,1079939,3047074,8597406,24257838, 68444231,193117503,544886995,1537415492, 4337865331,12239421132,34533905116,97438480950] |