[seqfan] Re: Two Sequences Related To Permutations of (1,2,...,n)

[Marc LeBrun]

 >=Edwin Clark
 >>=Leroy Quet
 >> ...the entire set P of the n of these plotted points would be on 
the perimeter of the convex hull of P.
 > Isn't this the same as permutations with exactly one local maximum.

Maybe I misunderstand, but doesn't something like 1 8 2 9 3 4 5 6 7 
have 1. all points on the hull, but also 2. more than one local maximum?

. . . x . . . . .
. x . . . . . . .
. . . . . . . . x
. . . . . . . x .
. . . . . . x . .
. . . . . x . . .
. . . . x . . . .
. . x . . . . . .
x . . . . . . . .