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.

A084078 Length of list created by n substitutions k -> Range[-abs(k+1), abs(k-1), 2] starting with {0}.

Table of values

n a(n)
0 1
1 2
2 4
3 10
4 24
5 66
6 172
7 498
8 1360
9 4066
10 11444
11 34970
12 100520
13 312066
14 911068
15 2862562
16 8457504
17 26824386
18 80006116
19 255680170
20 768464312
21 2471150402
22 7474561164
23 24161357010
24 73473471344
25 238552980386
26 728745517972

List of values

[1, 2, 4, 10, 24, 66, 172, 498, 1360, 4066, 11444, 34970, 100520, 312066, 911068, 2862562, 8457504, 26824386, 80006116, 255680170, 768464312, 2471150402, 7474561164, 24161357010, 73473471344, 238552980386, 728745517972]

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

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