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.

A058986 Sorting by prefix reversal (or "flipping pancakes"). You can only reverse segments that include the initial term of the current permutation; a(n) is the number of reversals that are needed to transform an arbitrary permutation of n letters to the identity permutation.

Table of values

n a(n)
1 0
2 1
3 3
4 4
5 5
6 7
7 8
8 9
9 10
10 11
11 13
12 14
13 15
14 16
15 17
16 18
17 19
18 20
19 22

List of values

[0, 1, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 22]

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

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