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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 12 |
| 6 | 30 |
| 7 | 76 |
| 8 | 196 |
| 9 | 512 |
| 10 | 1353 |
| 11 | 3610 |
| 12 | 9713 |
| 13 | 26324 |
| 14 | 71799 |
| 15 | 196938 |
| 16 | 542895 |
| 17 | 1503312 |
| 18 | 4179603 |
| 19 | 11662902 |
| 20 | 32652735 |
| 21 | 91695540 |
| 22 | 258215664 |
| 23 | 728997192 |
| 24 | 2062967382 |
| 25 | 5850674704 |
| 26 | 16626415975 |
| 27 | 47337954326 |
| 28 | 135015505407 |
| 29 | 385719506620 |
| 30 | 1103642686382 |
[1,1,1,2,5,12,30,76,196,512,1353,3610,9713,26324, 71799,196938,542895,1503312,4179603,11662902, 32652735,91695540,258215664,728997192,2062967382, 5850674704,16626415975,47337954326,135015505407, 385719506620,1103642686382] |