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

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =8a(5) =16a(6) =61a(7) =94a(8) =136a(9) =272a(10) =1385a(11) =2108a(12) =2840a(13) =3968a(14) =7936a(15) =50521a(16) =76474a(17) =100096a(18) =128704a(19) =176896a(20) =353792a(21) =2702765a(22) =4079408a(23) =5261120a(24) =6531968a(25) =8211200a(26) =11184128a(27) =22368256a(28) =199360981a(29) =300392854