HHC 2015 RPN programming Contest is now open

[Werner]

Gerson: on the 41, numeric values take up as many bytes as the digits and/or extra chars. So 123456 takes up 6 bytes and -1 E-3 takes up 5.

There is one exception: when the previous line contains a number, too, an invisible 'null' is inserted between the two, to separate the numbers. That takes up an extra byte.
On the 42S, this invisible null is present in all number entry lines, whether they are preceded by another number or not. And so the byte count for programs with number entry lines is different between the 41 and 42.

Cheers, Werner