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.

A122367 Dimension of 3-variable non-commutative harmonics (twisted derivative) of order n. The dimension of the space of non-commutative polynomials of degree n in 3 variables which are killed by all symmetric differential operators (where for a monomial w, d_{xi} ( xi w ) = w and d_{xi} ( xj w ) = 0 for i != j).

Table of values

n a(n)
0 1
1 2
2 5
3 13
4 34
5 89
6 233
7 610
8 1597
9 4181
10 10946
11 28657
12 75025
13 196418
14 514229
15 1346269
16 3524578
17 9227465
18 24157817
19 63245986
20 165580141
21 433494437
22 1134903170
23 2971215073
24 7778742049
25 20365011074
26 53316291173
27 139583862445
28 365435296162
29 956722026041

List of values

[1, 2, 5, 13, 34, 89, 233, 610, 1597, 4181, 10946, 28657, 75025, 196418, 514229, 1346269, 3524578, 9227465, 24157817, 63245986, 165580141, 433494437, 1134903170, 2971215073, 7778742049, 20365011074, 53316291173, 139583862445, 365435296162, 956722026041]

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

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