{
"$type": "site.standard.document",
"bskyPostRef": {
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"uri": "at://did:plc:46ti67tc37qcmwp2vaynk6fq/app.bsky.feed.post/3mett26j7dxo2"
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"path": "/blog/tech/2026-02-14-19-56_a286874_15_42.html",
"publishedAt": "2026-02-14T20:06:02.285Z",
"site": "http://blog.sesse.net",
"tags": [
"A286874"
],
"textContent": "The following 42 15-bit values form a 2-disjunctive matrix (that is, no union of two values contain or equal a third value), or equivalently, a superimposed code:\n\n\n 000000000011111\n 000000011100011\n 000000101101100\n 000001010110100\n 000001101010001\n 000001110001010\n 000010011011000\n 000100100110010\n 000110010000110\n 000110100001001\n 000111001100000\n 001000110000101\n 001010000110001\n 001010101000010\n 001011000001100\n 001100001010100\n 001100010101000\n 001101000000011\n 010001000101001\n 010010001000101\n 010010110100000\n 010011000010010\n 010100001001010\n 010100010010001\n 010101100000100\n 011000000100110\n 011000100011000\n 011001011000000\n 100001001000110\n 100010000101010\n 100010100010100\n 100011010000001\n 100100000100101\n 100100111000000\n 100101000011000\n 101000001001001\n 101000010010010\n 101001100100000\n 110000001110000\n 110000010001100\n 110000100000011\n 111110000000000\n\n\nThis shows that A286874 a(15) >= 42.\n\nIf I had to make a guess, I'd say the equality holds, but I have nowhere near the computing resources to actually find the answer for sure. Stay tuned for news about a(14), though.",
"title": "Steinar H. Gunderson: A286874(15) >= 42",
"updatedAt": "2026-02-14T18:56:00.000Z"
}