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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 9 |
| 5 | 10 |
| 6 | 31 |
| 7 | 70 |
| 8 | 160 |
| 9 | 171 |
| 10 | 277 |
| 11 | 630 |
| 12 | 724 |
| 13 | 3717 |
| 14 | 5542 |
| 15 | 5634 |
| 16 | 10656 |
| 17 | 12724 |
| 18 | 31954 |
[0,1,4,9,10,31,70,160,171,277,630,724,3717,5542, 5634,10656,12724,31954] |