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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 22 |
| 2 | 253 |
| 3 | 2046 |
| 4 | 13134 |
| 5 | 71368 |
| 6 | 341275 |
| 7 | 1473494 |
| 8 | 5848810 |
| 9 | 21628002 |
| 10 | 75261384 |
| 11 | 248403586 |
| 12 | 782547909 |
| 13 | 2365168542 |
| 14 | 6887441198 |
| 15 | 19393122562 |
| 16 | 52959869787 |
| 17 | 140631776582 |
| 18 | 363943223941 |
| 19 | 919706094494 |
| 20 | 2273411319069 |
| 21 | 5505315501136 |
| 22 | 13078268135683 |
| 23 | 30514651732686 |
| 24 | 70005101272876 |
[1,22,253,2046,13134,71368,341275,1473494,5848810, 21628002,75261384,248403586,782547909,2365168542, 6887441198,19393122562,52959869787,140631776582, 363943223941,919706094494,2273411319069, 5505315501136,13078268135683,30514651732686, 70005101272876] |