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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 20 |
| 5 | 40 |
| 6 | 78 |
| 7 | 147 |
| 8 | 272 |
| 9 | 495 |
| 10 | 890 |
| 11 | 1584 |
| 12 | 2796 |
| 13 | 4901 |
| 14 | 8540 |
| 15 | 14805 |
| 16 | 25552 |
| 17 | 43928 |
| 18 | 75258 |
| 19 | 128535 |
| 20 | 218920 |
| 21 | 371931 |
| 22 | 630454 |
| 23 | 1066464 |
| 24 | 1800600 |
| 25 | 3034825 |
| 26 | 5106868 |
| 27 | 8580897 |
| 28 | 14398412 |
| 29 | 24129160 |
| 30 | 40388070 |
| 31 | 67527579 |
| 32 | 112786496 |
| 33 | 188195271 |
| 34 | 313733810 |
| 35 | 522562320 |
| 36 | 869681412 |
[0,1,4,9,20,40,78,147,272,495,890,1584,2796,4901, 8540,14805,25552,43928,75258,128535,218920,371931, 630454,1066464,1800600,3034825,5106868,8580897, 14398412,24129160,40388070,67527579,112786496, 188195271,313733810,522562320,869681412] |