

A285485


Number of (n+1)extended Skolem sequences of order n.


0



0, 0, 2, 2, 0, 0, 44, 260, 0, 0, 33104, 203712, 0, 0, 75499696, 621309008, 0, 0, 492805156768, 5068810602400, 0, 0, 7346944632542720
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OFFSET

1,3


COMMENTS

Number of Rosa sequences of order n.
a(n) computed counting reflected solutions.


LINKS



EXAMPLE

For n = 3, there are 2 solutions: 1 1 3 0 2 3 2 and 2 3 2 0 3 1 1.
For n = 4, there are 2 solutions: 1 1 3 4 0 3 2 4 2 and 2 4 2 3 0 4 3 1 1.


CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS

a(1)a(18) from Jeppe Winther Larsen (jwl(AT)itu.dk), Oct 12 2009


STATUS

approved



