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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 22 |
| 3 | 464 |
| 4 | 9658 |
| 5 | 199666 |
| 6 | 4112922 |
| 7 | 84558014 |
| 8 | 1736623658 |
| 9 | 35646098566 |
| 10 | 731452470122 |
| 11 | 15006822709814 |
| 12 | 307859627711658 |
| 13 | 6315326642698966 |
| 14 | 129547066718721322 |
| 15 | 2657377349777550614 |
| 16 | 54509922224486463658 |
| 17 | 1118139793621467673366 |
| 18 | 22935894163202834676522 |
| 19 | 470473020119757115115414 |
[0,1,22,464,9658,199666,4112922,84558014, 1736623658,35646098566,731452470122, 15006822709814,307859627711658,6315326642698966, 129547066718721322,2657377349777550614, 54509922224486463658,1118139793621467673366, 22935894163202834676522,470473020119757115115414] |