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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 16 |
| 3 | 50 |
| 4 | 145 |
| 5 | 407 |
| 6 | 1177 |
| 7 | 3508 |
| 8 | 10677 |
| 9 | 32967 |
| 10 | 102719 |
| 11 | 321798 |
| 12 | 1011538 |
| 13 | 3186390 |
| 14 | 10050746 |
| 15 | 31730137 |
| 16 | 100228044 |
| 17 | 316713624 |
| 18 | 1001037551 |
| 19 | 3164497350 |
| 20 | 10004755379 |
| 21 | 31632975601 |
| 22 | 100021893197 |
| 23 | 316274794667 |
| 24 | 1000101078155 |
[3,16,50,145,407,1177,3508,10677,32967,102719, 321798,1011538,3186390,10050746,31730137, 100228044,316713624,1001037551,3164497350, 10004755379,31632975601,100021893197,316274794667, 1000101078155] |