Semiotic Reading of Numbers in the Pertamina Oil Governance Case: From Trial Facts to Mathematical Model

This paper presents two separate layers in the Pertamina oil governance case 2018–2023. The first layer is factual, based on the trial facts presented by the Attorney General's Office and the Supreme Audit Agency (BPK) in 2026, including the Cluster 1 state loss of Rp30.1 trillion from the Banyu Urip export scheme, the Orbit Terminal Merak tank network up to 22.4 thousand KL, the 506 public complaints recorded in early March 2025, and the final 15-year sentence of Muhammad Kerry Adrianto Riza. The second layer is semiotic, using a mathematical model as a reading tool. The parabola f(x) = -x² + 45x + 1/4 reaches its peak at x = 22.5 with f(22.5) = 506.5, while the centroid of g(x) = -2x + 90 is (15, 30). The paper argues that these numbers converge semiotically: 15 as the 2008–2023 father-to-son span and the 15-year sentence, and 30 as the Rp30.1 trillion state loss. The model does not prove corruption; it only reads the pattern of numbers in public discourse. Keywords: semiotics, Pertamina, corruption, mathematical model, centroid, Petral, public complaints