OFFSET
0,3
LINKS
EXAMPLE
a(3) = 36:
2 1 3
1 2 1
3 1 2
a(4) = 480:
2 1 3 4
1 2 1 3
3 1 2 1
4 3 1 2
a(5) = 9991:
3 1 2 4 5
1 3 1 2 4
2 1 3 1 2
4 2 1 3 1
5 4 2 1 3
PROG
(Python)
from itertools import permutations
from sympy import Matrix
def A351019(n): return 1 if n == 0 else min(Matrix([p[i:0:-1]+p[0:n-i] for i in range(n)]).per() for p in permutations(range(1, n+1))) # Chai Wah Wu, Jan 31 2022
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Stefano Spezia, Jan 29 2022
EXTENSIONS
a(9) from Alois P. Heinz, Jan 31 2022
a(10)-a(11) from Lucas A. Brown, Sep 06 2022
STATUS
approved