E.g.f. C(y,x) = cos(x) / sqrt(1 - sin(x)^2 - sin(y)^2).

Terms

a(0) =1a(1) =0a(2) =1a(3) =0a(4) =2a(5) =5a(6) =0a(7) =16a(8) =28a(9) =61a(10) =0a(11) =272a(12) =440a(13) =662a(14) =1385a(15) =0a(16) =7936a(17) =12448a(18) =17176a(19) =24568a(20) =50521a(21) =0a(22) =353792a(23) =546560a(24) =727232a(25) =949520a(26) =1326122a(27) =2702765a(28) =0a(29) =22368256