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.

A221741 a(n) = -4*(((n+1)^(n+1)-(n+1))/((n+1)-1)^2-1)/((-3+(-1)^n)*n).

Table of values

n a(n)
1 1
2 5
3 9
4 97
5 373
6 7625
7 48913
8 1513361
9 13717421
10 570623341
11 6698798233
12 350549891889
13 5057809205989
14 319164643134737
15 5465701947765793
16 403925909124187873
17 8008631808527689309
18 678470389458269406421
19 15287592943577781017641

List of values

[1, 5, 9, 97, 373, 7625, 48913, 1513361, 13717421, 570623341, 6698798233, 350549891889, 5057809205989, 319164643134737, 5465701947765793, 403925909124187873, 8008631808527689309, 678470389458269406421, 15287592943577781017641]