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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 52 |
| 4 | 233 |
| 5 | 1083 |
| 6 | 5100 |
| 7 | 24295 |
| 8 | 116918 |
| 9 | 565724 |
| 10 | 2752468 |
| 11 | 13446199 |
| 12 | 65884595 |
| 13 | 323738565 |
| 14 | 1594128852 |
| 15 | 7864002439 |
| 16 | 38855552063 |
| 17 | 192229773083 |
| 18 | 952108277471 |
| 19 | 4720386488466 |
| 20 | 23422582031478 |
| 21 | 116310271773159 |
| 22 | 577941027197706 |
| 23 | 2873420290878204 |
| 24 | 14293452937971562 |
| 25 | 71133050139234528 |
| 26 | 354145607242254419 |
[1,3,12,52,233,1083,5100,24295,116918,565724, 2752468,13446199,65884595,323738565,1594128852, 7864002439,38855552063,192229773083,952108277471, 4720386488466,23422582031478,116310271773159, 577941027197706,2873420290878204, 14293452937971562,71133050139234528, 354145607242254419] |