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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 127 |
| 3 | 2186 |
| 4 | 16383 |
| 5 | 78124 |
| 6 | 279935 |
| 7 | 823542 |
| 8 | 2097151 |
| 9 | 4782968 |
| 10 | 9999999 |
| 11 | 19487170 |
| 12 | 35831807 |
| 13 | 62748516 |
| 14 | 105413503 |
| 15 | 170859374 |
| 16 | 268435455 |
| 17 | 410338672 |
| 18 | 612220031 |
| 19 | 893871738 |
| 20 | 1279999999 |
| 21 | 1801088540 |
| 22 | 2494357887 |
| 23 | 3404825446 |
| 24 | 4586471423 |
| 25 | 6103515624 |
| 26 | 8031810175 |
[0,127,2186,16383,78124,279935,823542,2097151, 4782968,9999999,19487170,35831807,62748516, 105413503,170859374,268435455,410338672,612220031, 893871738,1279999999,1801088540,2494357887, 3404825446,4586471423,6103515624,8031810175] |