cp's OEIS Frontend

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.

A257859 a(n) = (2*n-1)*a(n-1) - a(n-2) with a(0)=2, a(1)=1.

Table of values

n a(n)
0 2
1 1
2 1
3 4
4 27
5 239
6 2602
7 33587
8 501203
9 8486864
10 160749213
11 3367246609
12 77285922794
13 1928780823241
14 51999796304713
15 1506065312013436
16 46636024876111803
17 1537482755599676063
18 53765260421112550402
19 1987777152825564688811
20 77469543699775910313227

List of values

[2, 1, 1, 4, 27, 239, 2602, 33587, 501203, 8486864, 160749213, 3367246609, 77285922794, 1928780823241, 51999796304713, 1506065312013436, 46636024876111803, 1537482755599676063, 53765260421112550402, 1987777152825564688811, 77469543699775910313227]