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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 30 |
| 4 | 118 |
| 5 | 407 |
| 6 | 1498 |
| 7 | 5289 |
| 8 | 19184 |
| 9 | 68832 |
| 10 | 247756 |
| 11 | 890523 |
| 12 | 3203084 |
| 13 | 11517675 |
| 14 | 41422044 |
| 15 | 148957388 |
| 16 | 535680672 |
| 17 | 1926390947 |
| 18 | 6927645818 |
| 19 | 24912983963 |
| 20 | 89591402294 |
| 21 | 322185988646 |
| 22 | 1158636174394 |
| 23 | 4166654317703 |
| 24 | 14984004032116 |
[1,10,30,118,407,1498,5289,19184,68832,247756, 890523,3203084,11517675,41422044,148957388, 535680672,1926390947,6927645818,24912983963, 89591402294,322185988646,1158636174394, 4166654317703,14984004032116] |