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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 27 |
| 5 | 65 |
| 6 | 146 |
| 7 | 346 |
| 8 | 788 |
| 9 | 1845 |
| 10 | 4239 |
| 11 | 9865 |
| 12 | 22758 |
| 13 | 52818 |
| 14 | 122072 |
| 15 | 282954 |
| 16 | 654528 |
| 17 | 1516221 |
| 18 | 3508817 |
| 19 | 8125763 |
| 20 | 18808494 |
| 21 | 43550500 |
| 22 | 100815652 |
| 23 | 233418699 |
| 24 | 540371471 |
| 25 | 1251079052 |
| 26 | 2896357943 |
| 27 | 6705591388 |
| 28 | 15524220275 |
| 29 | 35941069252 |
| 30 | 83208225215 |
[1,2,5,12,27,65,146,346,788,1845,4239,9865,22758, 52818,122072,282954,654528,1516221,3508817, 8125763,18808494,43550500,100815652,233418699, 540371471,1251079052,2896357943,6705591388, 15524220275,35941069252,83208225215] |