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.

A292880 Number of sequences of balls colored with at most n colors such that exactly three balls are of a color seen earlier in the sequence.

Table of values

n a(n)
1 1
2 32
3 633
4 10744
5 173705
6 2798376
7 45930577
8 777101648
9 13638044529
10 249079033360
11 4741200949001
12 94104123729672
13 1947270419971513
14 41985753920469464
15 942531024150018465
16 22009425078894009376
17 534085741053864862817
18 13454221423402868473728
19 351483652960252663137049
20 9512821482149972773978520

List of values

[1, 32, 633, 10744, 173705, 2798376, 45930577, 777101648, 13638044529, 249079033360, 4741200949001, 94104123729672, 1947270419971513, 41985753920469464, 942531024150018465, 22009425078894009376, 534085741053864862817, 13454221423402868473728, 351483652960252663137049, 9512821482149972773978520]

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

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