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.

A007846 There are three equivalent descriptions: 1. Number of (horizontally or vertically) connected arrays of 1..n on rectangular grid (otherwise zero) with only one local maximum. 2. Number of n-polyominoes labeled 1...n such that each successive labeled cell is the neighbor of a previously labeled cell. 3. Number of connected n-step paths on a rectangular lattice, diagonal or repeated steps not allowed.

Table of values

n a(n)
0 1
1 1
2 4
3 24
4 176
5 1504
6 14560
7 156768
8 1852512
9 23783264
10 329070176
11 4874845920
12 76898357216
13 1285734871520
14 22695759641440
15 421508294003424
16 8211642378316768

List of values

[1, 1, 4, 24, 176, 1504, 14560, 156768, 1852512, 23783264, 329070176, 4874845920, 76898357216, 1285734871520, 22695759641440, 421508294003424, 8211642378316768]

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

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