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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 72 |
| 3 | 992 |
| 4 | 16512 |
| 5 | 261632 |
| 6 | 4196352 |
| 7 | 67100672 |
| 8 | 1073774592 |
| 9 | 17179738112 |
| 10 | 274878431232 |
| 11 | 4398044413952 |
| 12 | 70368752566272 |
| 13 | 1125899873288192 |
| 14 | 18014398643699712 |
| 15 | 288230375614840832 |
| 16 | 4611686020574871552 |
| 17 | 73786976286248271872 |
| 18 | 1180591620751771041792 |
| 19 | 18889465931341141901312 |
[1,2,72,992,16512,261632,4196352,67100672, 1073774592,17179738112,274878431232,4398044413952, 70368752566272,1125899873288192,18014398643699712, 288230375614840832,4611686020574871552, 73786976286248271872,1180591620751771041792, 18889465931341141901312] |