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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 4 |
| 6 | 22 |
| 7 | 39 |
| 8 | 102 |
| 9 | 298 |
| 10 | 833 |
| 11 | 2105 |
| 12 | 6065 |
| 13 | 16665 |
| 14 | 45374 |
| 15 | 126224 |
| 16 | 348868 |
| 17 | 962054 |
| 18 | 2662783 |
| 19 | 7364465 |
| 20 | 20366371 |
| 21 | 56334291 |
| 22 | 155844294 |
| 23 | 431150954 |
| 24 | 1192657061 |
| 25 | 3299782775 |
| 26 | 9128883051 |
| 27 | 25255840216 |
| 28 | 69873935349 |
| 29 | 193313945656 |
| 30 | 534830511278 |
[0,1,3,3,4,22,39,102,298,833,2105,6065,16665, 45374,126224,348868,962054,2662783,7364465, 20366371,56334291,155844294,431150954,1192657061, 3299782775,9128883051,25255840216,69873935349, 193313945656,534830511278] |