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`and`(R = `*`(`+`(`*`(`/`(2, 3), `*`(a))), `+`(`*`(`/`(1, 2), `*`(sqrt(3))))), `and`(`*`(`+`(`*`(`/`(2, 3), `*`(a))), `+`(`*`(`/`(1, 2), `*`(sqrt(3))))) = `+`(`*`(`/`(1, 3), `*`(a, `*`(sqrt(3))))), `+... 

a = 36