OFFSET
0,3
LINKS
EXAMPLE
a(3) = 8:
1 2 3
2 1 2
3 2 1
a(4) = 12:
2 1 3 4
1 2 1 3
3 1 2 1
4 3 1 2
a(5) = 3:
1 5 2 3 4
5 1 5 2 3
2 5 1 5 2
3 2 5 1 5
4 3 2 5 1
PROG
(Python)
from itertools import permutations
from sympy import Matrix
def A348891(n): return min(d for d in (abs(Matrix([p[i:0:-1]+p[0:n-i] for i in range(n)]).det()) for p in permutations(range(1, n+1))) if d > 0)
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Lucas A. Brown, Sep 01 2022
STATUS
approved