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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 10 |
| 3 | 45 |
| 4 | 185 |
| 5 | 710 |
| 6 | 2766 |
| 7 | 10270 |
| 8 | 37444 |
| 9 | 132765 |
| 10 | 462327 |
| 11 | 1579563 |
| 12 | 5311361 |
| 13 | 17584084 |
| 14 | 57414594 |
| 15 | 185032557 |
| 16 | 589183035 |
| 17 | 1854974066 |
| 18 | 5778722817 |
| 19 | 17823440534 |
| 20 | 54458411332 |
| 21 | 164917654587 |
| 22 | 495219323844 |
| 23 | 1475145786950 |
| 24 | 4360576440676 |
| 25 | 12796007418881 |
| 26 | 37287660835368 |
| 27 | 107930276062786 |
[1,1,10,45,185,710,2766,10270,37444,132765,462327, 1579563,5311361,17584084,57414594,185032557, 589183035,1854974066,5778722817,17823440534, 54458411332,164917654587,495219323844, 1475145786950,4360576440676,12796007418881, 37287660835368,107930276062786] |