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.

A087440 Expansion of (1-2x-3x^2)/((1-2x)(1-4x)).

Table of values

n a(n)
0 1
1 4
2 13
3 46
4 172
5 664
6 2608
7 10336
8 41152
9 164224
10 656128
11 2622976
12 10488832
13 41949184
14 167784448
15 671113216
16 2684403712
17 10737516544
18 42949869568
19 171799085056
20 687195553792
21 2748780642304
22 10995119423488
23 43980471402496

List of values

[1, 4, 13, 46, 172, 664, 2608, 10336, 41152, 164224, 656128, 2622976, 10488832, 41949184, 167784448, 671113216, 2684403712, 10737516544, 42949869568, 171799085056, 687195553792, 2748780642304, 10995119423488, 43980471402496]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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