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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 23 |
| 4 | 88 |
| 5 | 363 |
| 6 | 1576 |
| 7 | 7091 |
| 8 | 32768 |
| 9 | 154588 |
| 10 | 741442 |
| 11 | 3604495 |
| 12 | 17721394 |
| 13 | 87960004 |
| 14 | 440165522 |
| 15 | 2218289051 |
| 16 | 11248850578 |
| 17 | 57354875692 |
| 18 | 293860786178 |
| 19 | 1512169500356 |
| 20 | 7811933144432 |
| 21 | 40499933496818 |
| 22 | 210643657689644 |
| 23 | 1098802033533295 |
| 24 | 5747266778089846 |
[1,3,7,23,88,363,1576,7091,32768,154588,741442, 3604495,17721394,87960004,440165522,2218289051, 11248850578,57354875692,293860786178, 1512169500356,7811933144432,40499933496818, 210643657689644,1098802033533295,5747266778089846] |