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| n | a(n) |
|---|---|
| 1 | 722 |
| 2 | 3706 |
| 3 | 12068 |
| 4 | 64224 |
| 5 | 211824 |
| 6 | 1159120 |
| 7 | 3850160 |
| 8 | 21563332 |
| 9 | 71908620 |
| 10 | 410324398 |
| 11 | 1371057344 |
| 12 | 7935278938 |
| 13 | 26539793884 |
| 14 | 155196079882 |
| 15 | 519275349560 |
| 16 | 3058687618974 |
| 17 | 10235947682204 |
| 18 | 60595706198366 |
| 19 | 202797923521632 |
[722,3706,12068,64224,211824,1159120,3850160, 21563332,71908620,410324398,1371057344,7935278938, 26539793884,155196079882,519275349560, 3058687618974,10235947682204,60595706198366, 202797923521632] |