OFFSET
1,3
FORMULA
a(n) = A130152(n,floor(n/2)).
EXAMPLE
a(4) = 9: 1342, 1423, 1432, 2314, 2413, 3124, 3142, 3214, 3412.
a(5) = 23: 12453, 12534, 12543, 13425, 13524, 14235, 14253, 14325, 14523, 21453, 21534, 21543, 23145, 23154, 24135, 24153, 31245, 31254, 31425, 31524, 32145, 32154, 34125.
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jan 28 2019
STATUS
approved