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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 46 |
| 4 | 265 |
| 5 | 1519 |
| 6 | 8560 |
| 7 | 47578 |
| 8 | 264076 |
| 9 | 1461439 |
| 10 | 8075011 |
| 11 | 44596708 |
| 12 | 246189961 |
| 13 | 1358762089 |
| 14 | 7498499272 |
| 15 | 41378660380 |
| 16 | 228330571360 |
| 17 | 1259923712821 |
| 18 | 6952163820391 |
| 19 | 38361311420962 |
| 20 | 211673092313329 |
| 21 | 1167984733037851 |
| 22 | 6444783128779528 |
| 23 | 35561432547881926 |
[0,1,7,46,265,1519,8560,47578,264076,1461439, 8075011,44596708,246189961,1358762089,7498499272, 41378660380,228330571360,1259923712821, 6952163820391,38361311420962,211673092313329, 1167984733037851,6444783128779528, 35561432547881926] |