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`and`(S = `+`(`*`(`^`(a, 2)), `-`(`*`(`/`(1, 4), `*`(`*`(4, `/`(1, 4)), `*`(Pi, `*`(`^`(a, 2))))))), `and`(`+`(`*`(`^`(a, 2)), `-`(`*`(`/`(1, 4), `*`(`*`(4, `/`(1, 4)), `*`(Pi, `*`(`^`(a, 2))))))) = `...