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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 8 |
| 7 | 29 |
| 8 | 85 |
| 9 | 211 |
| 10 | 464 |
| 11 | 938 |
| 12 | 1808 |
| 13 | 3459 |
| 14 | 6826 |
| 15 | 14198 |
| 16 | 30960 |
| 17 | 69143 |
| 18 | 154433 |
| 19 | 340006 |
| 20 | 734561 |
| 21 | 1561313 |
| 22 | 3286129 |
| 23 | 6900097 |
| 24 | 14542101 |
| 25 | 30855957 |
| 26 | 65908862 |
| 27 | 141395972 |
| 28 | 303745077 |
| 29 | 651763377 |
| 30 | 1395140215 |
| 31 | 2978858672 |
[1,1,1,1,1,2,8,29,85,211,464,938,1808,3459,6826, 14198,30960,69143,154433,340006,734561,1561313, 3286129,6900097,14542101,30855957,65908862, 141395972,303745077,651763377,1395140215, 2978858672] |