Beefy Boxes and Bandwidth Generously Provided by pair Networks
Pathologically Eclectic Rubbish Lister

Re: Re: Formulas for certain 'fangs'

by Anonymous Monk
on Jun 11, 2002 at 17:26 UTC ( #173579=note: print w/replies, xml ) Need Help??

in reply to Re: Vampire Numbers
in thread Vampire Numbers

a couple of general formulas such as the the fangs

x = 25.10^k+1 y = 100(10^(k+1)+52)/25

give the vampire

v = xy = (10^(k+1)+52)10^(k+2)+100(10^k+1+52)/25 = x'.10^(k+2)+t
= 8(26+5.10^k)(1+25.10^k)

where x' denotes x with digits reversed

Replies are listed 'Best First'.
by Anonymous Monk on Jun 11, 2002 at 17:29 UTC
    153 is also a plus perfect number or 'armstrong' number


Log In?

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://173579]
[marto]: I can relate to that somewhat, I'm a light sleeper and frequently get woken up by kids doing much the same as your cats
[jedikaiti]: Yea, the kids (& the cats) are good at that
talexb is having a hard time with Windows losing DNS info for Perlmonks when voting. CB works fine. Ugh.
[jedikaiti]: how odd

How do I use this? | Other CB clients
Other Users?
Others cooling their heels in the Monastery: (14)
As of 2017-07-25 15:14 GMT
Find Nodes?
    Voting Booth?
    I came, I saw, I ...

    Results (374 votes). Check out past polls.