1 + 2 + 3 + 4 + ⋯

1 + 2 + 3 + 4 + more is the infinite series formed by summing every positive integer in order. Because its partial sums are the triangular numbers n(n+1)/2, which grow without bound, the series diverges and has no sum in the ordinary sense. Even so, certain regularization methods used in mathematics and theoretical physics, including zeta function regularization and Ramanujan summation, assign the divergent series the finite value negative one twelfth. That assigned value is a property of the regularization method applied to the series, not a sum in the everyday sense of adding up an infinite list of numbers.