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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 257 |
| 3 | 9843 |
| 4 | 131074 |
| 5 | 976565 |
| 6 | 5038851 |
| 7 | 20176807 |
| 8 | 67108868 |
| 9 | 193710249 |
| 10 | 500000005 |
| 11 | 1178973851 |
| 12 | 2579890182 |
| 13 | 5302249693 |
| 14 | 10330523399 |
| 15 | 19221679695 |
| 16 | 34359738376 |
| 17 | 59293938257 |
| 18 | 99179645193 |
| 19 | 161343848899 |
| 20 | 256000000010 |
| 21 | 397140023301 |
| 22 | 603634608907 |
[0,1,257,9843,131074,976565,5038851,20176807, 67108868,193710249,500000005,1178973851, 2579890182,5302249693,10330523399,19221679695, 34359738376,59293938257,99179645193,161343848899, 256000000010,397140023301,603634608907] |