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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 30 |
| 4 | 126 |
| 5 | 534 |
| 6 | 2275 |
| 7 | 9667 |
| 8 | 41089 |
| 9 | 174660 |
| 10 | 742428 |
| 11 | 3155820 |
| 12 | 13414405 |
| 13 | 57020437 |
| 14 | 242375995 |
| 15 | 1030264362 |
| 16 | 4379330826 |
| 17 | 18615162402 |
| 18 | 79127219431 |
| 19 | 336345003127 |
| 20 | 1429697162869 |
| 21 | 6077194423824 |
| 22 | 25832248272072 |
| 23 | 109804788896376 |
[1,7,30,126,534,2275,9667,41089,174660,742428, 3155820,13414405,57020437,242375995,1030264362, 4379330826,18615162402,79127219431,336345003127, 1429697162869,6077194423824,25832248272072, 109804788896376] |