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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 14 |
| 4 | 42 |
| 5 | 103 |
| 6 | 289 |
| 7 | 690 |
| 8 | 1771 |
| 9 | 4206 |
| 10 | 10142 |
| 11 | 23449 |
| 12 | 54786 |
| 13 | 123528 |
| 14 | 279480 |
| 15 | 619206 |
| 16 | 1366405 |
| 17 | 2969071 |
| 18 | 6425534 |
| 19 | 13727775 |
| 20 | 29187555 |
| 21 | 61439660 |
| 22 | 128620370 |
| 23 | 267044222 |
| 24 | 551527679 |
| 25 | 1130806020 |
| 26 | 2306746335 |
| 27 | 4676096006 |
| 28 | 9432394144 |
| 29 | 18920266428 |
| 30 | 37776372312 |
[1,1,5,14,42,103,289,690,1771,4206,10142,23449, 54786,123528,279480,619206,1366405,2969071, 6425534,13727775,29187555,61439660,128620370, 267044222,551527679,1130806020,2306746335, 4676096006,9432394144,18920266428,37776372312] |