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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 14 |
| 5 | 46 |
| 6 | 282 |
| 7 | 1118 |
| 8 | 5962 |
| 9 | 21974 |
| 10 | 100324 |
| 11 | 384813 |
| 12 | 1770579 |
| 13 | 7304326 |
| 14 | 33789034 |
| 15 | 142823462 |
| 16 | 650681108 |
| 17 | 2776615816 |
| 18 | 12494221594 |
| 19 | 53928255898 |
| 20 | 241817051980 |
| 21 | 1054482471250 |
| 22 | 4720387107791 |
| 23 | 20718599970171 |
| 24 | 92576815674458 |
[1,2,4,14,46,282,1118,5962,21974,100324,384813, 1770579,7304326,33789034,142823462,650681108, 2776615816,12494221594,53928255898,241817051980, 1054482471250,4720387107791,20718599970171, 92576815674458] |