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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 1 |
| 7 | 4 |
| 8 | 4 |
| 9 | 9 |
| 10 | 9 |
| 11 | 18 |
| 12 | 18 |
| 13 | 31 |
| 14 | 31 |
| 15 | 51 |
| 16 | 51 |
| 17 | 79 |
| 18 | 79 |
| 19 | 119 |
| 20 | 119 |
| 21 | 173 |
| 22 | 173 |
| 23 | 248 |
| 24 | 248 |
| 25 | 347 |
| 26 | 347 |
| 27 | 480 |
| 28 | 480 |
| 29 | 654 |
| 30 | 654 |
| 31 | 883 |
| 32 | 883 |
| 33 | 1178 |
| 34 | 1178 |
| 35 | 1561 |
| 36 | 1561 |
| 37 | 2049 |
| 38 | 2049 |
| 39 | 2674 |
| 40 | 2674 |
| 41 | 3464 |
| 42 | 3464 |
| 43 | 4464 |
| 44 | 4464 |
| 45 | 5717 |
| 46 | 5717 |
| 47 | 7290 |
| 48 | 7290 |
| 49 | 9246 |
| 50 | 9246 |
| 51 | 11680 |
| 52 | 11680 |
[0,0,0,0,1,1,4,4,9,9,18,18,31,31,51,51,79,79,119, 119,173,173,248,248,347,347,480,480,654,654,883, 883,1178,1178,1561,1561,2049,2049,2674,2674,3464, 3464,4464,4464,5717,5717,7290,7290,9246,9246, 11680,11680] |