Luhn Algorithm Visa help?

[omera51]

I'm trying to get the full number of a Visa card with the Luhn Algorithm. I have the following digits...
4266****8038
The middle 5 (5 because Visas have at either 13 or 16 digits) are unknown. Does anybody know how to solve this?
Edit: So far I have this... 4 4 6 3 * * * * * 7 0 6 8 after doubling the alternate digits.

[Deep_ps]

Do they help with paypal verification?

[LiqFan]

Graham King » Luhn formula

Maybe that helps.

[omera51]

Graham King » Luhn formula

Maybe that helps.

Don't see how it would work with missing digits. Thanks anyway! :P

[Nikentic]

What does this number actually do ?
because i just guessed 2 numbers.. :P

[Mynamehere]

You can't do this it's impossible. I'll show you . . .
4 2 6 6 A B C D E 8 0 3 8
Double Alternate Digit starting from 2nd right Alternating.
Drop down original digits that were not doubled.
Add everything together. If it's divisible by 10 with no remainder it's a valid card.

56 + A + 2B + C + 2D + E = Number divisible by 10.

A,B,C,D, and E could be all sorts of numbers.