Beefy Boxes and Bandwidth Generously Provided by pair Networks
XP is just a number
 
PerlMonks  

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


Comment on Re: Re: Formulas for certain 'fangs'
153
by Anonymous Monk on Jun 11, 2002 at 17:29 UTC
    153 is also a plus perfect number or 'armstrong' number

    153=1^3+5^3+3^3=1+125+27

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://173579]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others chilling in the Monastery: (13)
As of 2014-09-19 16:11 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    How do you remember the number of days in each month?











    Results (143 votes), past polls