h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

A very good question; so how does it work?

I suppose we could ask Jim Lynne who wrote the code for h2g2. But that would be cheating.

No! Dont think like that. Ask! Ask! Thats what i say!

Thanks for writing the entry, it is an interesting subject.

When will you ask Mr Lynne? I am sure he will be happy to tell you.

You could ask him yourself, if you like. He's U6.

Oh, and his surname is Lynn, rather than Lynne as I said earlier.

I think he might take more notice if you asked him , after all it was your guide entry, i will if you wont though; i might come back and ask if you for a translation of his answer though.

" ..come back and ask for a translation of his answer though."

Btw thanks! " Mr Lynn"

I posted a message for Jim Lynn, i hope someone will answer it.
This is what i asked him:
http://www.bbc.co.uk/dna/h2g2/brunel/A43234292

and this is what i originally intended:
http://www.bbc.co.uk/dna/h2g2/brunel/A43234265




Those entries were within 2 minutes of each other and there is a 30 difference leaving aside the final digit.
I shall try and compare,with two short entries in succession .

Hey i think i have figured how to calculate the entry number; but how it actually works is still somewhat of a mystery.


if i add up any guide number that i come accross they always add up to a number ending with nine

the last digit is always whatever digit is needed to make the number add up to nine

i think you are right every guide entry number is ten digits apart, giving scope for a checksum digit at the end

when i worked this out i thought maybe there was a zero at the end of a number ending in 9 so that the guide entry format of ( eight at the moment ) numbers stays the same; however i can see from the examples you have given that this is not the case ( although these guide entry numbers are in three number format )

am i anywhere near right?????

What about A199 ?

Oh, I see. 1 + 9 + 9 = 19 which ends in 9.

well it ends in nine so it fits ; it must be a two digit number that has nine added wich signifies the checksum has been done; what i thought earlier about zero i think is not right , i think maybe it is like this entry number which has nine so add a nine .

What do you think?

Here's an interesting thing:

A12340
A12341
A12342
A12343
A12344
A12345
A12346
A12347
A12348
A12349

h2g2 automatically converted the last one to a link, because it is a valid number for an entry. But that particular entry is the personal space of a researcher so when you click on it, it brings you not to the entry but to their personal space.

And I can tell that that particular researcher registered on h2g2 on either the day it was launched or the next day, because his User number is less than 30,000.

Yes i supose it is because of what you suggested in your entry; each entry number is 10 digits apart to give scope for the checksum digit at the endm , which is 1 to 9 right ? So the numbers in between dont count and are lost forever or just whitespace kind of.

This only applies to the 2nd digit from the left , the tens digit , in every guide entry number so for the hundreds thousands tenthousands etc ... there are no missing numbers

Yes you are right, very odd, there is no reference to that guide entry number is there ?

A123450
A123451
A123452
A123453
A123454
A123455
A123456
A123457
A123458
A123459

?

A1234560
A1234561
A1234562
A1234563
A1234564
A1234565
A1234566
A1234567
A1234568
A1234569

Still no reply from Jim Lynn
Hey thanks my friend for introducing me to the wonderful world of the checksum.
That last link is a strange one, just a bbc search page; would be interesting to see the first few pages in order, or maybe not



XSUM

I think the A numbers are not exclusive to h2g2, they are used for all the DNA sites.