This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 55 |
| 4 | 368 |
| 5 | 2449 |
| 6 | 16280 |
| 7 | 108199 |
| 8 | 719072 |
| 9 | 4778785 |
| 10 | 31758632 |
| 11 | 211059991 |
| 12 | 1402652240 |
| 13 | 9321678001 |
| 14 | 61949553848 |
| 15 | 411701328775 |
| 16 | 2736064645568 |
| 17 | 18183205205569 |
| 18 | 120841059834440 |
| 19 | 803079631825399 |
| 20 | 5337067516093232 |