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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 21 |
| 4 | 82 |
| 5 | 317 |
| 6 | 1221 |
| 7 | 4699 |
| 8 | 18080 |
| 9 | 69561 |
| 10 | 267625 |
| 11 | 1029641 |
| 12 | 3961362 |
| 13 | 15240637 |
| 14 | 58635641 |
| 15 | 225590199 |
| 16 | 867918160 |
| 17 | 3339160721 |
| 18 | 12846826845 |
| 19 | 49425880861 |
| 20 | 190157283842 |
| 21 | 731596320957 |
| 22 | 2814686695261 |
| 23 | 10829006332499 |
| 24 | 41662675404240 |
| 25 | 160289731905481 |
| 26 | 616686228261665 |
[1,5,21,82,317,1221,4699,18080,69561,267625, 1029641,3961362,15240637,58635641,225590199, 867918160,3339160721,12846826845,49425880861, 190157283842,731596320957,2814686695261, 10829006332499,41662675404240,160289731905481, 616686228261665] |