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.
Table of n, a(n), showing exponents of prime factors of a(n), and the prime decomposition of a(n)-1 and a(n)+1 for n = 1..6:
Exponents
n a(n) 2.3.5.7 a(n)-1 a(n)+1
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1 2097152 21 7^2, 127, 337 3^2, 43, 5419
2 13436928 11.8 7^2, 274223 11^2, 111049
3 46656000 9.6.3 13^2, 359, 769 7, 19^2, 37, 499
4 1073741824 30 3^2, 7, 11, 31, 151, 331 5^2, 13, 41, 61, 1321
5 1360800000 8.5.5.1 13^2, 107, 75253 11^2, 167, 67343
6 12884901888 32.1 11, 13^3, 563, 947 19^2, 35692249
(* Load function f from A025487, then: *) Select[Union@ Flatten@ f[12], AllTrue[# + {-1, 1}, Not @* SquareFreeQ] &]
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