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Triangle T(n,k) read by rows, where T(n,k) = number of times the permanent of a real n X n (0,1)-matrix takes the value k, for n >= 0, 0 <= k <= n!.
9

%I #30 Sep 20 2024 07:48:39

%S 0,1,1,1,9,6,1,265,150,69,18,9,0,1,27713,13032,10800,4992,4254,1440,

%T 1536,576,648,24,288,96,48,0,72,0,0,0,16,0,0,0,0,0,1,10363361,3513720,

%U 4339440,2626800,3015450,1451400,1872800,962400,1295700,425400,873000

%N Triangle T(n,k) read by rows, where T(n,k) = number of times the permanent of a real n X n (0,1)-matrix takes the value k, for n >= 0, 0 <= k <= n!.

%C The last element of each row is 1, corresponding to the n X n "all 1" matrix with permanent = n!. The first 4 rows were provided by _Wouter Meeussen_. The 6th row was computed by _Gordon F. Royle_: 13906734081, 2722682160, 4513642920, 3177532800, 4466769300, 2396826720, 3710999520, 2065521600, 3253760550, 1468314000, 2641593600, 1350475200, 2210277600, 1034061120,... .

%H Hugo Pfoertner, <a href="/A089479/b089479.txt">Table of n, a(n) for n = 0..159</a> (rows 0..5, flattened)

%F From _Geoffrey Critzer_, Dec 20 2023: (Start)

%F Sum_{k=1..n!} T(n,k) = A227414(n).

%F For n>2, T(n,n!-(n-1)!) = n^2, the number of matrices with exactly one 0 entry. (End)

%e Triangle begins:

%e 0, 1;

%e 1, 1;

%e 9, 6, 1;

%e 265, 150, 69, 18, 9, 0, 1;

%e 27713, 13032, 10800, 4992, 4254, 1440, 1536, 576, 648, 24, 288,

%e 96, 48, 0, 72, 0, 0, 0, 16, 0, 0, 0, 0, 0, 1;

%e ...

%Y T(n,0) = A088672(n), T(n,1) = A089482(n). The n-th row of the table contains A087983(n) nonzero entries. For n>2 A089477(n) gives the position of the first zero entry in the n-th row.

%Y Cf. A089480 (occurrence counts for permanents of non-singular (0,1)-matrices), A089481 (occurrence counts for permanents of singular (0,1)-matrices).

%Y Cf. A000290, A038507 (row lengths), A002416 (row sums).

%Y Cf. A036781, A089478.

%K nonn,tabf

%O 0,5

%A _Hugo Pfoertner_, Nov 05 2003

%E Edited by _Alois P. Heinz_, Dec 20 2023