Steve from blackpenredpen answers a real Oxford University maths admissions interview question set by Oxford Mathematician (and interviewing tutor) Dr Tom Crawford. The question looks at the divergence of the sum of the reciprocals of the prime numbers, using the Fundamental Theorem of Arithmetic, the divergence of the Harmonic Series (1/n), and the Basel Problem (sum of 1/n2 equals pi-squared over 6).
This is part 2 of the interview – you can find part 1 on Gabriel’s Horn here.