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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 4 |
| 6 | 13 |
| 7 | 18 |
| 8 | 47 |
| 9 | 84 |
| 10 | 177 |
| 11 | 320 |
| 12 | 639 |
| 13 | 1120 |
| 14 | 2077 |
| 15 | 3581 |
| 16 | 6235 |
| 17 | 10395 |
| 18 | 17344 |
| 19 | 27940 |
| 20 | 44848 |
| 21 | 70180 |
| 22 | 108921 |
| 23 | 165817 |
| 24 | 250256 |
| 25 | 371558 |
| 26 | 546960 |
| 27 | 794363 |
| 28 | 1143783 |
| 29 | 1628190 |
| 30 | 2299144 |
| 31 | 3214042 |
| 32 | 4459495 |
| 33 | 6133164 |
| 34 | 8375820 |
| 35 | 11349269 |
| 36 | 15278595 |
| 37 | 20423345 |
| 38 | 27136816 |
| 39 | 35827488 |
| 40 | 47037493 |
| 41 | 61397294 |
| 42 | 79726515 |
| 43 | 102977471 |
| 44 | 132370606 |
| 45 | 169322488 |
| 46 | 215620140 |
| 47 | 273339320 |
| 48 | 345063648 |
| 49 | 433787088 |
| 50 | 543198659 |
| 51 | 677563207 |
| 52 | 842079818 |
| 53 | 1042751237 |
| 54 | 1286826668 |
| 55 | 1582652314 |
| 56 | 1940231900 |
| 57 | 2371051392 |
| 58 | 2888771603 |
| 59 | 3509044867 |
| 60 | 4250358055 |
| 61 | 5133832789 |
| 62 | 6184270777 |
| 63 | 7429930460 |
[1,0,1,1,3,4,13,18,47,84,177,320,639,1120,2077, 3581,6235,10395,17344,27940,44848,70180,108921, 165817,250256,371558,546960,794363,1143783, 1628190,2299144,3214042,4459495,6133164,8375820, 11349269,15278595,20423345,27136816,35827488, 47037493,61397294,79726515,102977471,132370606, 169322488,215620140,273339320,345063648,433787088, 543198659,677563207,842079818,1042751237, 1286826668,1582652314,1940231900,2371051392, 2888771603,3509044867,4250358055,5133832789, 6184270777,7429930460] |