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A340432 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = 4^(2*n*k) * Product_{a=1..n} Product_{b=1..k} (1 - sin(a*Pi/(2*n+1))^2 * cos(b*Pi/(2*k+1))^2).

%I A340432 #11 Jan 08 2021 06:41:23
%S A340432 1,1,1,1,13,1,1,121,181,1,1,1093,18281,2521,1,1,9841,1690781,2803921,
%T A340432 35113,1,1,88573,152963281,2732887529,430503601,489061,1,1,797161,
%U A340432 13755675781,2555011015201,4447515497881,66102491401,6811741,1
%N A340432 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = 4^(2*n*k) * Product_{a=1..n} Product_{b=1..k} (1 - sin(a*Pi/(2*n+1))^2 * cos(b*Pi/(2*k+1))^2).
%e A340432 Square array begins:
%e A340432   1,     1,         1,             1,                 1, ...
%e A340432   1,    13,       121,          1093,              9841, ...
%e A340432   1,   181,     18281,       1690781,         152963281, ...
%e A340432   1,  2521,   2803921,    2732887529,     2555011015201, ...
%e A340432   1, 35113, 430503601, 4447515497881, 43384923739812577, ...
%o A340432 (PARI) default(realprecision, 120);
%o A340432 {T(n, k) = round(4^(2*n*k)*prod(a=1, n, prod(b=1, k, 1-(sin(a*Pi/(2*n+1))*cos(b*Pi/(2*k+1)))^2)))}
%Y A340432 Main diagonal gives A340295.
%Y A340432 Cf. A340427, A340428, A340430.
%K A340432 nonn,tabl
%O A340432 0,5
%A A340432 _Seiichi Manyama_, Jan 07 2021