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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 87 |
| 6 | 308 |
| 7 | 1129 |
| 8 | 4258 |
| 9 | 16401 |
| 10 | 64399 |
| 11 | 256816 |
| 12 | 1037571 |
| 13 | 4239492 |
| 14 | 17496610 |
| 15 | 72839052 |
| 16 | 305557831 |
| 17 | 1290667314 |
| 18 | 5485660832 |
| 19 | 23445450636 |
| 20 | 100712243095 |
| 21 | 434628533918 |
| 22 | 1883622613990 |
| 23 | 8195129117207 |
| 24 | 35783068474745 |
| 25 | 156763846451702 |
| 26 | 688897134052493 |
| 27 | 3036057675681138 |
| 28 | 13416279582944950 |
[1,1,3,8,26,87,308,1129,4258,16401,64399,256816, 1037571,4239492,17496610,72839052,305557831, 1290667314,5485660832,23445450636,100712243095, 434628533918,1883622613990,8195129117207, 35783068474745,156763846451702,688897134052493, 3036057675681138,13416279582944950] |