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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 24 |
| 6 | 76 |
| 7 | 236 |
| 8 | 785 |
| 9 | 2634 |
| 10 | 9106 |
| 11 | 31870 |
| 12 | 113371 |
| 13 | 407438 |
| 14 | 1479526 |
| 15 | 5415700 |
| 16 | 19970119 |
| 17 | 74096864 |
| 18 | 276466199 |
| 19 | 1036598162 |
| 20 | 3903844089 |
| 21 | 14760093096 |
| 22 | 56006631629 |
| 23 | 213206289068 |
| 24 | 814045174247 |
| 25 | 3116569685906 |
| 26 | 11961635892951 |
[1,2,3,9,24,76,236,785,2634,9106,31870,113371, 407438,1479526,5415700,19970119,74096864, 276466199,1036598162,3903844089,14760093096, 56006631629,213206289068,814045174247, 3116569685906,11961635892951] |