@boomerang,
No, There's no such thread because I'm living in a very small country, and the questions are written in the local language so there's no more than 1000 users, at the most...
But I did ask the same question on a local internet forum - and it seems like they also think it has something to do with Indigo. So we're all stuck...
And as for your suggestion - I've tried 83 and 666...
The thing is - It supposed to be a specific number, and all I can find about indigo, visible spectrum, etc. pretty sums up in ranges.
On the other hand - It's about Newton and I couldn't find anything else that would make sense, either.