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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 9 |
| 2 | 20 |
| 3 | 44 |
| 4 | 96 |
| 5 | 209 |
| 6 | 455 |
| 7 | 990 |
| 8 | 2154 |
| 9 | 4686 |
| 10 | 10194 |
| 11 | 22176 |
| 12 | 48241 |
| 13 | 104942 |
| 14 | 228287 |
| 15 | 496607 |
| 16 | 1080300 |
| 17 | 2350043 |
| 18 | 5112193 |
| 19 | 11120867 |
| 20 | 24191904 |
| 21 | 52626132 |
| 22 | 114480851 |
| 23 | 249037213 |
| 24 | 541745915 |
| 25 | 1178493097 |
| 26 | 2563648273 |
| 27 | 5576861234 |
| 28 | 12131688091 |
| 29 | 26390804748 |
| 30 | 57409535261 |
[4,9,20,44,96,209,455,990,2154,4686,10194,22176, 48241,104942,228287,496607,1080300,2350043, 5112193,11120867,24191904,52626132,114480851, 249037213,541745915,1178493097,2563648273, 5576861234,12131688091,26390804748,57409535261] |