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a(n) is the permanent of the n X n matrix whose generic element is abs(s(i+3,j)) where 1<= i,j <= n and s(r,c) is a Stirling number of the 1st kind.
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%I #10 Jul 07 2024 13:48:14

%S 1,6,564,306096,564505464,2625790073064,27398936076368184,

%T 584616801786680299848,23661396380641487392884216,

%U 1707763221685376355443856875112,208836912138505980452592269085336072,41452742977042741902029728999187937151368,12878287403223722868703002883355321706487115016

%N a(n) is the permanent of the n X n matrix whose generic element is abs(s(i+3,j)) where 1<= i,j <= n and s(r,c) is a Stirling number of the 1st kind.

%e a(3) = 306096:

%e [ 6, 11, 6]

%e [ 24, 50, 35]

%e [120, 274, 225]

%t a[n_]:=Permanent[Table[Abs[StirlingS1[i+3,j]],{i,n},{j,n}]]; Join[{1},Array[a,12]]

%Y Cf. A000400 (determinant), A048994, A132393, A372343.

%K nonn

%O 0,2

%A _Stefano Spezia_, Jul 06 2024