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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.

A173380 Number of n-step walks on square lattice (no points repeated, no adjacent points unless consecutive in path).

Table of values

n a(n)
0 1
1 4
2 12
3 28
4 68
5 164
6 396
7 940
8 2244
9 5324
10 12668
11 29940
12 71012
13 167468
14 396172
15 932628
16 2201636
17 5175268
18 12195660
19 28632804
20 67374292
21 158017740
22 371354012
23 870197548
24 2042809996
25 4783292988
26 11218303476
27 26250429540
28 61514573604
29 143857013260
30 336865512780
31 787374453524
32 1842579846180

List of values

[1, 4, 12, 28, 68, 164, 396, 940, 2244, 5324, 12668, 29940, 71012, 167468, 396172, 932628, 2201636, 5175268, 12195660, 28632804, 67374292, 158017740, 371354012, 870197548, 2042809996, 4783292988, 11218303476, 26250429540, 61514573604, 143857013260, 336865512780, 787374453524, 1842579846180]

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

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