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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 17 |
| 5 | 51 |
| 6 | 198 |
| 7 | 687 |
| 8 | 2836 |
| 9 | 10749 |
| 10 | 46067 |
| 11 | 184597 |
| 12 | 812310 |
| 13 | 3381735 |
| 14 | 15171550 |
| 15 | 64957583 |
| 16 | 295681089 |
| 17 | 1293489193 |
| 18 | 5954355415 |
| 19 | 26493181563 |
| 20 | 123052625899 |
| 21 | 555024101601 |
| 22 | 2596786703611 |
| 23 | 11844164816717 |
| 24 | 55752005243735 |
| 25 | 256658725835629 |
| 26 | 1214315074819775 |
| 27 | 5633998302373761 |
| 28 | 26772387983328833 |
[1,1,2,5,17,51,198,687,2836,10749,46067,184597, 812310,3381735,15171550,64957583,295681089, 1293489193,5954355415,26493181563,123052625899, 555024101601,2596786703611,11844164816717, 55752005243735,256658725835629,1214315074819775, 5633998302373761,26772387983328833] |