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.

A197424 Number of subsets of {1, 2, ..., 4*n + 2} which do not contain two numbers whose difference is 4.

Table of values

n a(n)
0 4
1 36
2 225
3 1600
4 10816
5 74529
6 509796
7 3496900
8 23961025
9 164249856
10 1125736704
11 7716041281
12 52886200900
13 362488284900
14 2484529385121
15 17029223715904
16 116720020119616
17 800010960336225
18 5483356589096100
19 37583485459535236
20 257601040852192129

List of values

[4, 36, 225, 1600, 10816, 74529, 509796, 3496900, 23961025, 164249856, 1125736704, 7716041281, 52886200900, 362488284900, 2484529385121, 17029223715904, 116720020119616, 800010960336225, 5483356589096100, 37583485459535236, 257601040852192129]

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

Content is available under The OEIS End-User License Agreement.