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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 26 |
| 4 | 108 |
| 5 | 461 |
| 6 | 2034 |
| 7 | 9151 |
| 8 | 41846 |
| 9 | 193537 |
| 10 | 903807 |
| 11 | 4252089 |
| 12 | 20128339 |
| 13 | 95773027 |
| 14 | 457664391 |
| 15 | 2195009182 |
| 16 | 10560857316 |
| 17 | 50950249692 |
| 18 | 246393307834 |
| 19 | 1194059857715 |
| 20 | 5797379229221 |
| 21 | 28194069637441 |
| 22 | 137319055635798 |
| 23 | 669708375761934 |
| 24 | 3270145776993544 |
| 25 | 15985543779112186 |
| 26 | 78221161921702212 |
[1,2,7,26,108,461,2034,9151,41846,193537,903807, 4252089,20128339,95773027,457664391,2195009182, 10560857316,50950249692,246393307834, 1194059857715,5797379229221,28194069637441, 137319055635798,669708375761934,3270145776993544, 15985543779112186,78221161921702212] |