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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 7 |
| 4 | 12 |
| 5 | 23 |
| 6 | 55 |
| 7 | 116 |
| 8 | 228 |
| 9 | 443 |
| 10 | 885 |
| 11 | 1812 |
| 12 | 3743 |
| 13 | 7635 |
| 14 | 15391 |
| 15 | 30890 |
| 16 | 62033 |
| 17 | 124795 |
| 18 | 251329 |
| 19 | 506102 |
| 20 | 1018194 |
| 21 | 2045892 |
| 22 | 4106530 |
| 23 | 8236843 |
| 24 | 16514499 |
| 25 | 33102119 |
| 26 | 66336493 |
| 27 | 132908840 |
| 28 | 266228896 |
| 29 | 533159832 |
| 30 | 1067501475 |
| 31 | 2136981261 |
| 32 | 4277279486 |
| 33 | 8560149475 |
| 34 | 17129767749 |
| 35 | 34275609936 |
| 36 | 68578490158 |
| 37 | 137203118904 |
| 38 | 274484024181 |
| 39 | 549098750459 |
| 40 | 1098416535730 |
| 41 | 2197199475635 |
| 42 | 4395011194670 |
[1,1,4,7,12,23,55,116,228,443,885,1812,3743,7635, 15391,30890,62033,124795,251329,506102,1018194, 2045892,4106530,8236843,16514499,33102119, 66336493,132908840,266228896,533159832,1067501475, 2136981261,4277279486,8560149475,17129767749, 34275609936,68578490158,137203118904,274484024181, 549098750459,1098416535730,2197199475635, 4395011194670] |