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A365646
a(n) is the permanent of the n X n matrix M(n) whose generic M[i, j] = j*(10^i - 1)/9 with 1 <= i, j <= n.
1
1, 1, 44, 43956, 781361856, 217042789550400, 868170290030441798400, 47267044397174696636039097600, 33612120124091913005718848881499750400, 302509080814318135934642422882028113666502246400, 33612120087118580872578956587618207930922159448149975040000
OFFSET
0,3
COMMENTS
For n > 1, the matrix M(n) is singular.
EXAMPLE
a(3) = 43956:
[ 1, 2, 3]
[ 11, 22, 33]
[111, 222, 333]
MATHEMATICA
M[i_, j_]:=j(10^i-1)/9; Join[{1}, Table[Permanent[Table[M[i, j], {i, n}, {j, n}]], {n, 10}]]
PROG
(PARI) a(n) = matpermanent(matrix(n, n, i, j, j*(10^i - 1)/9)); \\ Michel Marcus, Sep 17 2023
CROSSREFS
Cf. A365644.
Sequence in context: A183749 A119096 A131484 * A308325 A305997 A277840
KEYWORD
nonn
AUTHOR
Stefano Spezia, Sep 14 2023
STATUS
approved