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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 10 |
| 3 | 54 |
| 4 | 238 |
| 5 | 990 |
| 6 | 4030 |
| 7 | 16254 |
| 8 | 65278 |
| 9 | 261630 |
| 10 | 1047550 |
| 11 | 4192254 |
| 12 | 16773118 |
| 13 | 67100670 |
| 14 | 268419070 |
| 15 | 1073709054 |
| 16 | 4294901758 |
| 17 | 17179738110 |
| 18 | 68719214590 |
| 19 | 274877382654 |
| 20 | 1099510579198 |
| 21 | 4398044413950 |
| 22 | 17592181850110 |
| 23 | 70368735789054 |
| 24 | 281474959933438 |
| 25 | 1125899873288190 |
[0,10,54,238,990,4030,16254,65278,261630,1047550, 4192254,16773118,67100670,268419070,1073709054, 4294901758,17179738110,68719214590,274877382654, 1099510579198,4398044413950,17592181850110, 70368735789054,281474959933438,1125899873288190] |