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.

A019472 Weak preference orderings of n alternatives, i.e., orderings that have indifference between at least two alternatives.

Table of values

n a(n)
0 0
1 0
2 1
3 7
4 51
5 421
6 3963
7 42253
8 505515
9 6724381
10 98618763
11 1582715773
12 27612565995
13 520631327581
14 10554164679243
15 228975516609853
16 5294731892093355
17 130015079601039901
18 3379132289551117323
19 92679942218919579133
20 2675254894236207563115
21 81073734056332364441821

List of values

[0, 0, 1, 7, 51, 421, 3963, 42253, 505515, 6724381, 98618763, 1582715773, 27612565995, 520631327581, 10554164679243, 228975516609853, 5294731892093355, 130015079601039901, 3379132289551117323, 92679942218919579133, 2675254894236207563115, 81073734056332364441821]

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

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