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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 39 |
| 4 | 163 |
| 5 | 698 |
| 6 | 3093 |
| 7 | 13980 |
| 8 | 63817 |
| 9 | 295250 |
| 10 | 1378577 |
| 11 | 6473083 |
| 12 | 30601533 |
| 13 | 145413606 |
| 14 | 693468104 |
| 15 | 3320340108 |
| 16 | 15949166440 |
| 17 | 76800820187 |
| 18 | 370781922113 |
| 19 | 1793994166695 |
| 20 | 8695586394877 |
| 21 | 42223940576424 |
| 22 | 205352852892638 |
| 23 | 1000056842156015 |
| 24 | 4876643618508198 |
| 25 | 23808301200207172 |
| 26 | 116355162538349843 |
[1,3,10,39,163,698,3093,13980,63817,295250, 1378577,6473083,30601533,145413606,693468104, 3320340108,15949166440,76800820187,370781922113, 1793994166695,8695586394877,42223940576424, 205352852892638,1000056842156015,4876643618508198, 23808301200207172,116355162538349843] |