If you can guess what the next numbers in each sequence will be and what the formula for the sequence is that would be great, I will reply which guesses are correct as I have the numbers up to thousands for each. But I'm most interested in the formula for the sequence. Thanks.

I've run into a weird problem with parallel ports. I have been making devices that connect to the parallel port using EPP mode since 2001. Although a few PCI cards and multi-I/O chips had problems, it all seemed to settle down by 2006, and they all worked. I've been using Dell motherboard ports and 3 different generations of SIIG PCI ports for years with no trouble.

Then, a customer had a Startech PCIe parport that didn't work. This used the Oxford OXPCIe952 chip. I got a SIIG PCIe card (used the same chip) and got the same result.

What happens is that as long as the control register has bit 5 low, for write mode, everything works as expected. But, if I put ctrl reg bit 5 high, for read mode, and read the EPP data port with an INB instruction, it does NOT generate the DATASTB/ pulse. So, it appears there is no way to read data back from the target device in EPP mode.

I got a Saba PCIe card from Amazon, and it worked immediately. I assume various printers and scanners read data back in EPP mode to sense toner and error conditions. It is hard to believe that an error this big could go into production. The EPP spec is really poorly written, there are timing diagrams with no numbers anywhere on them, and some multi-I/O chips even violate the implied order of signals, like producing the strobe signals before the data lines or WRITE/ are asserted. But, this chip just seems to not work at all when trying to read in EPP mode, and I can't find anything that I'm doing wrong.

I've got a feeling that these sequences would pass whatever statistical tests you'd need to conclude "the sequence of natural numbers with some type of random noise thrown in" pretty well. ??

That sequence2 from above of sexy prime midpoints, is actually a subset sequence of the midpoints of sexy primes (it isn't all the +-3 sexy prime midpoints). The additional criteria for sequence2 that makes it a subset sequence is that there are no other n-x and n+y where x=y and x and y are both prime and n-x is prime.

The full sequence of sexy prime center points is a combination of sequence2 in addition to another new sequence called "Z(count)=2" sequence:

and the "Z(count)=2" sequence: (for numbers where one of the two Z(count)'s has an x value of 3, all, of the numbers have a single n+-3 sexy prime pair, which is the whole sequence except for the number 12 which has an x value of 5, and is the center point of a 5x2=10 prime pair, not a 2x3 sexy prime pair)

It is interesting because the full list of sexy prime pairs is composed of the set of sequence2, which is restricted to having only a single primal pair, combined with the Z(count)=2 sequence, which is restricted to having only two primal pairs, one of which has an x value of 3, and a y value of n+(n-3)

So the two Z(x y) pairs of the "Z(count)=2 sequence" are:

Z(n-3,n+3) Z(3,n+(n-3))

So all sexy prime pairs have a midpoint that meets the condition of having either just a single primal pair, or at most two primal pairs, with one of them having an x value of 3.

Restated in (more normal?) math terminology:

There are only two types of sexy prime pair midpoints:

midpoint type1: for a midpoint n, there is exactly one x where n-x and n+x are both prime, and where n-(n-x) is prime (x=3)

midpoint type2: for a midpoint n, there are exactly two x where n-x and n+x are both prime, and where n-(n-x) is prime x=3 and x=n-(n-x)

I guess you didn't see what I wrote, so we are in the same boat, but at least I am learning about math while you are complaining when you could just as easily follow through with your meaningless threat to killfile me, which for some reason you think I care about, in fact I prefer anyone who spends their replies complaining or attempting to impersonate Bill Slowman etc would killfile me to save thoughts for better purposes.

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