Hp Algorithm to create random numbers

[DavidM]

As Albert also indicated, the internal seed is actually 15 decimal digits. Here's another series of examples that might help to show what's happening.

First, I'll set the seed to a nice number with RDZ so that this can be easily replicated:

1E-13 RDZ

The internal seed now has a value of 000000000000001.

Executing RAND at this stage causes the following:
new_seed = (000000000000001 x 2851130928467) MOD 10^15 = 002851130928467
RAND result is normalized to 2.85113092846E-3 *

Next RAND:
new_seed = (002851130928467 x 2851130928467) MOD 10^15 = 261097470970089
RAND result is normalized to 0.26109747097

Next RAND:
new_seed = (261097470970089 x 2851130928467) MOD 10^15 = 335429755623563
RAND result is normalized to 0.335429755623

Next RAND:
new_seed = (335429755623563 x 2851130928467) MOD 10^15 = 468090732667921
RAND result is normalized to 0.468090732667

* The normalization step appears to shift out any leading zeros before truncating the last three digits.