PPL 099 / 177 permanent IDsPrize Problem Ledger · PPLChecked 2026.07.27
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Prize Problem LedgerKimberling rewardsPPL 099Kimberling #12 · Prime-separator first-row gaps

Permanent problem IDPPL 099

Verified openIndependentconjecture

Number theory

Kimberling #12 · Prime-separator first-row gaps

In Kimberling’s prime-separator array, prove or disprove that the successive differences in the first row are bounded.

prime separator arraybounded gapsinteger sequences
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The problem

In Kimberling’s prime-separator array, prove or disprove that the successive differences in the first row are bounded.

Open since2007sequence-record date
Last checked2026.07.27Catalog verification
02

Reward offers

Offer 01$25Clark Kimberling
Personal offer

Be first to publish a solution in a refereed journal, or submit a short proof that Kimberling accepts as correct and complete. For solutions after 1 January 2025, Kimberling says the stated amount will be donated in the solver’s name to the Online Encyclopedia of Integer Sequences; it is not direct cash to the solver.

Current post-2025 form: a donation to OEIS in the solver’s name.

Award source ↗
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Sources & reading

3 unique reference linksSponsor’s live rewards page OEIS A129258 OEIS A129259
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