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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 26 |
| 5 | 76 |
| 6 | 248 |
| 7 | 824 |
| 8 | 2766 |
| 9 | 9616 |
| 10 | 34586 |
| 11 | 126604 |
| 12 | 469054 |
| 13 | 1763768 |
| 14 | 6740582 |
| 15 | 26050180 |
| 16 | 101538790 |
| 17 | 399330656 |
| 18 | 1585705250 |
| 19 | 6344919988 |
| 20 | 25545244242 |
| 21 | 103470060008 |
| 22 | 421830613640 |
| 23 | 1729216715736 |
| 24 | 7121389942094 |
| 25 | 29457398594096 |
| 26 | 122424027677428 |
| 27 | 510904322626572 |
| 28 | 2139753669413014 |
[1,2,4,10,26,76,248,824,2766,9616,34586,126604, 469054,1763768,6740582,26050180,101538790, 399330656,1585705250,6344919988,25545244242, 103470060008,421830613640,1729216715736, 7121389942094,29457398594096,122424027677428, 510904322626572,2139753669413014] |