Πεψενθε 

`and`(p = `*`(`+`(`+`(8, 15), 17), `/`(1, 2)), `*`(`+`(`+`(8, 15), 17), `/`(1, 2)) = 20) 

`and`(S = sqrt(`*`(`+`(`*`(5, `*`(`*`(20, 12)))), 3)), `and`(sqrt(`*`(`+`(`*`(5, `*`(`*`(20, 12)))), 3)) = 60, 60 = `*`(a, `*`(b, `*`(c, `*`(`/`(`+`(`*`(4, `*`(R)))))))))) 

`and`(R = `+`(`/`(`*`(17, `*`(`*`(8, 15))), `*`(`*`(4, 60)))), `+`(`/`(`*`(17, `*`(`*`(8, 15))), `*`(`*`(4, 60)))) = `/`(17, 2)) 

d = 17