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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 22 |
| 6 | 82 |
| 7 | 333 |
| 8 | 1448 |
| 9 | 6572 |
| 10 | 30490 |
| 11 | 143552 |
| 12 | 683101 |
| 13 | 3274826 |
| 14 | 15796897 |
| 15 | 76581875 |
| 16 | 372868101 |
| 17 | 1822236628 |
| 18 | 8934910362 |
| 19 | 43939164263 |
| 20 | 216651036012 |
| 21 | 1070793308942 |
| 22 | 5303855973849 |
| 23 | 26323064063884 |
| 24 | 130878392115834 |
| 25 | 651812979669234 |
| 26 | 3251215493161062 |
| 27 | 16240020734253127 |
| 28 | 81227147768301723 |
| 29 | 406770970805865187 |
| 30 | 2039375198751047333 |
[1,1,3,7,22,82,333,1448,6572,30490,143552,683101, 3274826,15796897,76581875,372868101,1822236628, 8934910362,43939164263,216651036012,1070793308942, 5303855973849,26323064063884,130878392115834, 651812979669234,3251215493161062, 16240020734253127,81227147768301723, 406770970805865187,2039375198751047333] |