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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 348 |
| 3 | 495 |
| 4 | 1371 |
| 5 | 3255 |
| 6 | 4088 |
| 7 | 9140 |
| 8 | 20096 |
| 9 | 24947 |
| 10 | 54383 |
| 11 | 118235 |
| 12 | 146508 |
| 13 | 318072 |
| 14 | 690228 |
| 15 | 855015 |
| 16 | 1854963 |
| 17 | 4024047 |
| 18 | 4984496 |
| 19 | 10812620 |
| 20 | 23454968 |
| 21 | 29052875 |
| 22 | 63021671 |
| 23 | 136706675 |
| 24 | 169333668 |
| 25 | 367318320 |
| 26 | 796785996 |
| 27 | 986950047 |
| 28 | 2140889163 |
[0,348,495,1371,3255,4088,9140,20096,24947,54383, 118235,146508,318072,690228,855015,1854963, 4024047,4984496,10812620,23454968,29052875, 63021671,136706675,169333668,367318320,796785996, 986950047,2140889163] |