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.

A027057 a(n) = (1/2) * A027052(n, 2n-1).

Table of values

n a(n)
2 1
3 2
4 4
5 9
6 21
7 51
8 128
9 329
10 861
11 2285
12 6132
13 16606
14 45313
15 124446
16 343680
17 953753
18 2658133
19 7436541
20 20875972
21 58783892
22 165989825
23 469903672
24 1333359488
25 3791535934
26 10802911297
27 30836181436
28 88169413364
29 252500533673
30 724182805389
31 2079862921763
32 5981150599872

List of values

[1, 2, 4, 9, 21, 51, 128, 329, 861, 2285, 6132, 16606, 45313, 124446, 343680, 953753, 2658133, 7436541, 20875972, 58783892, 165989825, 469903672, 1333359488, 3791535934, 10802911297, 30836181436, 88169413364, 252500533673, 724182805389, 2079862921763, 5981150599872]