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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 13 |
| 3 | 52 |
| 4 | 210 |
| 5 | 843 |
| 6 | 3373 |
| 7 | 13492 |
| 8 | 53970 |
| 9 | 215883 |
| 10 | 863533 |
| 11 | 3454132 |
| 12 | 13816530 |
| 13 | 55266123 |
| 14 | 221064493 |
| 15 | 884257972 |
| 16 | 3537031890 |
| 17 | 14148127563 |
| 18 | 56592510253 |
| 19 | 226370041012 |
| 20 | 905480164050 |
| 21 | 3621920656203 |
| 22 | 14487682624813 |
| 23 | 57950730499252 |
[3,13,52,210,843,3373,13492,53970,215883,863533, 3454132,13816530,55266123,221064493,884257972, 3537031890,14148127563,56592510253,226370041012, 905480164050,3621920656203,14487682624813, 57950730499252] |