0,3

a(n) is even for all n > 1.

Is this sequence strictly increasing for n > 0?

Table of n, a(n) for n=0..12.

Programming Puzzles & Code Golf Stack Exchange, Permutations such that no k+2 points fall on any polynomial of degree k

For n = 4, the 18 different permutations are:

[1,2,4,3],[1,3,2,4],[1,3,4,2],[1,4,2,3],[2,1,3,4],[2,1,4,3],

[2,3,1,4],[2,4,1,3],[2,4,3,1],[3,1,2,4],[3,1,4,2],[3,2,4,1],

[3,4,1,2],[3,4,2,1],[4,1,3,2],[4,2,1,3],[4,2,3,1],[4,3,1,2].

Cf. A300002.

Sequence in context: A151449 A045664 A106520 * A318249 A093045 A317887

Adjacent sequences: A301799 A301800 A301801 * A301803 A301804 A301805

nonn,more

Peter Kagey, Mar 26 2018

a(0) and a(10)-a(12) from Peter J. Taylor, Mar 28 2018

approved