Fibonacci
Add the last two, get the next.
A member of the Fibonacci sequence: F₀=0, F₁=1, and every term after is the sum of the previous two — like 8, 144 or 832040.
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Only 30 Fibonacci numbers live in the range (0 through 832040), a mere 0.003%. The sequence grows exponentially by the golden ratio φ ≈ 1.618, so the gaps widen geometrically — it doesn't thin out linearly, it exits exponentially.
The golden ratio φ = (1+√5)/2 hides in the limit of the sequence: the ratio of consecutive terms converges to φ. That's why sunflower seeds and pinecone scales so often come in Fibonacci counts — it's the optimal packing for circular space.
Trivia: exactly 9 Fibonacci primes live in the range — 2, 3, 5, 13, 89, 233, 1597, 28657 and 514229. And the only square Fibonacci numbers are 0, 1 and 144 (proving that was once a notoriously hard problem).