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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 10 |
| 2 | 38 |
| 3 | 161 |
| 4 | 750 |
| 5 | 3799 |
| 6 | 20739 |
| 7 | 121141 |
| 8 | 752681 |
| 9 | 4949969 |
| 10 | 34312195 |
| 11 | 249798408 |
| 12 | 1904026799 |
| 13 | 15153517600 |
| 14 | 125621420076 |
| 15 | 1082409498473 |
| 16 | 9675240317432 |
| 17 | 89561442387221 |
| 18 | 857209445230483 |
| 19 | 8471058440432651 |
| 20 | 86318636142516675 |
| 21 | 905868823242467245 |
| 22 | 9779990840117785293 |
[3,10,38,161,750,3799,20739,121141,752681,4949969, 34312195,249798408,1904026799,15153517600, 125621420076,1082409498473,9675240317432, 89561442387221,857209445230483,8471058440432651, 86318636142516675,905868823242467245, 9779990840117785293] |