OFFSET
0,3
COMMENTS
Conjecture: a(n) is the minimal permanent of an n X n symmetric Toeplitz matrix having 0 on the main diagonal and all the first n-1 primes off-diagonal. - Stefano Spezia, Jul 06 2024
EXAMPLE
a(4) = 529:
[0, 2, 3, 5]
[2, 0, 2, 3]
[3, 2, 0, 2]
[5, 3, 2, 0]
MATHEMATICA
a[n_]:=Permanent[Table[If[i == j, 0, Prime[Abs[i - j]]], {i, 1, n}, {j, 1, n}]]; Join[{1}, Array[a, 17]]
PROG
(PARI) a(n) = matpermanent(matrix(n, n, i, j, if (i==j, 0, prime(abs(i-j))))); \\ Michel Marcus, Jun 28 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefano Spezia, Jun 27 2024
STATUS
approved