7x2 – 44x + 12 = pn
⇒ 7x2 – 42x – 2x + 12 = pn
⇒ (7x – 2)(x – 6) = pn
Let 7x – 2 be the prime number
⇒ x – 6 must be the same prime number or 1
Now, x – 6 = 1
⇒ x = 7
Then, 7x – 2 = 7 × 7 – 2
= 47, which is a prime number
Further, 7x – 2 and x – 6 must be the same prime numbers
∴ 7x – 2 = x – 6
⇒ 6x = – 4
⇒ x = –2/3,
Hence, x ∉ Z
∴ pn = 47
p = 47 and n = 1