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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 28 |
| 5 | 110 |
| 6 | 519 |
| 7 | 2749 |
| 8 | 16317 |
| 9 | 106425 |
| 10 | 755425 |
| 11 | 5781956 |
| 12 | 47384170 |
| 13 | 413331955 |
| 14 | 3818838624 |
| 15 | 37213866876 |
| 16 | 381108145231 |
| 17 | 4088785729738 |
| 18 | 45829237977692 |
| 19 | 535340785268513 |
| 20 | 6502943193997922 |
| 21 | 81984445333355812 |
| 22 | 1070848034863526547 |
| 23 | 14467833457108560375 |
| 24 | 201894571410270034773 |
[1,1,3,8,28,110,519,2749,16317,106425,755425, 5781956,47384170,413331955,3818838624,37213866876, 381108145231,4088785729738,45829237977692, 535340785268513,6502943193997922, 81984445333355812,1070848034863526547, 14467833457108560375,201894571410270034773] |