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| n | a(n) |
|---|---|
| 1 | 376 |
| 2 | 1128 |
| 3 | 3684 |
| 4 | 13336 |
| 5 | 49056 |
| 6 | 186500 |
| 7 | 710304 |
| 8 | 2755840 |
| 9 | 10693364 |
| 10 | 42087616 |
| 11 | 165680800 |
| 12 | 659882692 |
| 13 | 2629088000 |
| 14 | 10575205872 |
| 15 | 42553878500 |
| 16 | 172546960864 |
| 17 | 699893575232 |
| 18 | 2856015808196 |
| 19 | 11657898710352 |
| 20 | 47806906114000 |
[376,1128,3684,13336,49056,186500,710304,2755840, 10693364,42087616,165680800,659882692,2629088000, 10575205872,42553878500,172546960864,699893575232, 2856015808196,11657898710352,47806906114000] |