Concept
The Euler–Mascheroni constant
The constant gap between the harmonic partial sums and the natural logarithm, near enough 0.5772. It is what the naive sieve heuristic for the primes gets wrong by, and whether it is irrational is not known.
Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.
A sum whose terms vanish and whose total does not
Add a half, a third, a quarter, and keep going. The terms shrink to nothing and the total passes every number there is — but so slowly that no computation will ever watch it happen.
How long until every one turns up
Draw at random from six equally likely kinds until all six have appeared. The wait is not six draws, and it is not sixty; it is fourteen point seven, and the number is a harmonic sum wearing a hat.
Named alongside it
The objects these essays reach for when they reach for this one.
Harmonic seriesApproximationBlock stackingCollisionConvergenceConvergence rateDivergenceExpectationHarmonicsLimitLinearityLogarithm