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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 23 |
| 3 | 101 |
| 4 | 436 |
| 5 | 1871 |
| 6 | 8014 |
| 7 | 34309 |
| 8 | 146868 |
| 9 | 628708 |
| 10 | 2691401 |
| 11 | 11521603 |
| 12 | 49323052 |
| 13 | 211148530 |
| 14 | 903912916 |
| 15 | 3869592721 |
| 16 | 16565477544 |
| 17 | 70915744968 |
| 18 | 303585747088 |
| 19 | 1299631069856 |
| 20 | 5563637060865 |
| 21 | 23817572559345 |
| 22 | 101961496787621 |
[1,5,23,101,436,1871,8014,34309,146868,628708, 2691401,11521603,49323052,211148530,903912916, 3869592721,16565477544,70915744968,303585747088, 1299631069856,5563637060865,23817572559345, 101961496787621] |