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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 6 |
| 5 | 40 |
| 6 | 208 |
| 7 | 798 |
| 8 | 3122 |
| 9 | 15038 |
| 10 | 77830 |
| 11 | 381798 |
| 12 | 1819998 |
| 13 | 8925172 |
| 14 | 45280900 |
| 15 | 231030138 |
| 16 | 1171823534 |
| 17 | 5962836408 |
| 18 | 30668699312 |
| 19 | 158951012362 |
| 20 | 825830001086 |
| 21 | 4298605879552 |
| 22 | 22459588992656 |
| 23 | 117842770179898 |
| 24 | 620193719988230 |
| 25 | 3271151667546526 |
| 26 | 17291851589803030 |
| 27 | 91629268113394082 |
| 28 | 486633483668452306 |
| 29 | 2589396122840425628 |
| 30 | 13802082307489152876 |
| 31 | 73692343820697785462 |
| 32 | 394098991084750746722 |
[1,2,2,6,40,208,798,3122,15038,77830,381798, 1819998,8925172,45280900,231030138,1171823534, 5962836408,30668699312,158951012362,825830001086, 4298605879552,22459588992656,117842770179898, 620193719988230,3271151667546526, 17291851589803030,91629268113394082, 486633483668452306,2589396122840425628, 13802082307489152876,73692343820697785462, 394098991084750746722] |