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.

A064049 Number of possible arrangements of numbers 1 to n*(n+1)/2 in a triangle of n rows so that each row and each diagonal is increasing or decreasing.

Table of values

n a(n)
1 1
2 6
3 24
4 180
5 4212
6 461064
7 302693712
8 1383863258256
9 49604541999616656
10 15532699074331383195984
11 46930820867492201530663876176
12 1498790780922460190338294851221480784
13 550147065342809949572433566527924149475155792
14 2507733133290710762054763613438903427360533018661706960

List of values

[1, 6, 24, 180, 4212, 461064, 302693712, 1383863258256, 49604541999616656, 15532699074331383195984, 46930820867492201530663876176, 1498790780922460190338294851221480784, 550147065342809949572433566527924149475155792, 2507733133290710762054763613438903427360533018661706960]

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

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