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Square array T(n,k), n >= 1, k >= 1, read by antidiagonals, where T(n,k) = sqrt( Product_{a=1..n} Product_{b=1..k} (4*sin((2*a-1)*Pi/(2*n))^2 + 4*sin((2*b-1)*Pi/k)^2) ).
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%I #26 Feb 14 2021 05:52:08

%S 2,8,2,14,36,2,36,50,200,2,82,256,224,1156,2,200,722,2916,1058,6728,2,

%T 478,2916,9922,38416,5054,39204,2,1156,10082,80000,155682,527076,

%U 24200,228488,2,2786,38416,401998,2775556,2540032,7311616,115934,1331716,2

%N Square array T(n,k), n >= 1, k >= 1, read by antidiagonals, where T(n,k) = sqrt( Product_{a=1..n} Product_{b=1..k} (4*sin((2*a-1)*Pi/(2*n))^2 + 4*sin((2*b-1)*Pi/k)^2) ).

%e Square array begins:

%e 2, 8, 14, 36, 82, 200, ...

%e 2, 36, 50, 256, 722, 2916, ...

%e 2, 200, 224, 2916, 9922, 80000, ...

%e 2, 1156, 1058, 38416, 155682, 2775556, ...

%e 2, 6728, 5054, 527076, 2540032, 105125000, ...

%e 2, 39204, 24200, 7311616, 41934482, 4115479104, ...

%o (PARI) default(realprecision, 120);

%o T(n, k) = round(sqrt(prod(a=1, n, prod(b=1, k, 4*sin((2*a-1)*Pi/(2*n))^2+4*sin((2*b-1)*Pi/k)^2))));

%Y Columns 1..7 give A007395, A341543, A231087, A341544, A231485, A341545, A230033.

%Y Main diagonal gives A341535.

%Y Cf. A340475.

%K nonn,tabl

%O 1,1

%A _Seiichi Manyama_, Feb 13 2021