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A351021
Minimal permanent of an n X n symmetric Toeplitz matrix using the first n prime numbers.
8
1, 2, 13, 166, 4009, 169469, 10949857, 1078348288, 138679521597, 24402542896843, 5348124003487173
OFFSET
0,2
EXAMPLE
a(3) = 166:
3 2 5
2 3 2
5 2 3
a(4) = 4009:
3 2 5 7
2 3 2 5
5 2 3 2
7 5 2 3
a(5) = 169469:
5 2 3 7 11
2 5 2 3 7
3 2 5 2 3
7 3 2 5 2
11 7 3 2 5
PROG
(Python)
from itertools import permutations
from sympy import Matrix, prime
def A351021(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(prime(i) for i in range(1, n+1))) # Chai Wah Wu, Jan 31 2022
CROSSREFS
Cf. A348891, A350939, A350955, A351022 (maximal).
Sequence in context: A360601 A177448 A258224 * A078363 A143851 A088316
KEYWORD
nonn,hard,more
AUTHOR
Stefano Spezia, Jan 29 2022
EXTENSIONS
a(9) and a(10) from Lucas A. Brown, Sep 04 2022
STATUS
approved