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| n | a(n) |
|---|---|
| 1 | 28 |
| 2 | 99 |
| 3 | 350 |
| 4 | 1238 |
| 5 | 4379 |
| 6 | 15490 |
| 7 | 54793 |
| 8 | 193821 |
| 9 | 685609 |
| 10 | 2425226 |
| 11 | 8578828 |
| 12 | 30346157 |
| 13 | 107344412 |
| 14 | 379712753 |
| 15 | 1343169821 |
| 16 | 4751236703 |
| 17 | 16806698494 |
| 18 | 59450861306 |
| 19 | 210297394895 |
| 20 | 743891565706 |
| 21 | 2631390949017 |
| 22 | 9308101672049 |
| 23 | 32925839761497 |
[28,99,350,1238,4379,15490,54793,193821,685609, 2425226,8578828,30346157,107344412,379712753, 1343169821,4751236703,16806698494,59450861306, 210297394895,743891565706,2631390949017, 9308101672049,32925839761497] |