In Volume 14, Number 1 DETHMaster submitted an
excellent TI-82 progie to generate credit card numbers.
However, I found that the program had a rather glaring
bug: It was unable to generate Discover credit card num-
bers. Discover uses the prefix 6011, which caused the
program to fall into an endless loop. This modification
should solve that error: Immeditate preceding the line
0->S, insert:
:If [A](1,2)=0
:Then
:1->F
:Else
:0->F
And the line that reads:
:[A](2,P)+S->S
Should be changed to:
:[A](2,P)+S+F->S
I hope this solves any problems!
- Crumpet
2600, v14n3
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While reading the article entitled "How to
Generate Credit Card Numbers On a Calculator"
in the Spring issue of 2600 I found a series
of mistakes (most likely typographical) in the
code.
The idea of generating CC numbers no a TI-82 to
learn about the Luhn algorithm is a great idea
and it's a shame that a small mistake might ruin
that chance for the curious reader. The problem is
where the code assigns numbers to the second
matrix (it starts at the bottom of the first
column). The part where it says:
[A](1,1) * 2 -> [A](2,1)
[A](1,2) -> [A](2,2)
[A](1,1) * 2 -> [A](2,3)
[A](1,2) -> [A](2,4)
etc. should read:
[A](1,1) * 2 -> [A](2,)
[A](1,2) -> [A](2,2)
[A](1,3) * 2 -> [A](2,3)
[A](1,4) -> [A](2,4)
etc. and, of course, the first matrix
should keep incrementing with the second
After this small correction is applied, the
program works perfectly.
- Mutter
2600, v14n3