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# phil1882

Member Since 27 Apr 2012
Offline Last Active Yesterday, 07:20 PM

### In Topic: Relatively prime

03 May 2015 - 11:21 PM

if you really wanna see something bizarre, the Riemann zeta function tells us that the sequence 1 +2 +3 +4 +5 .... = -1/12.

### In Topic: Relatively prime

03 May 2015 - 11:16 PM

the equation

1/1^2 +1/2^2 +1/3^2 ... is well known to be pi^2/6, and is equivalent to 1/(1-1/2^2) *1/(1-1/3^2) *1/(1-1/5^2) ...

### In Topic: Cosmetic Surgery and the Worm

30 April 2015 - 02:49 PM

Spoiler for simple case
Spoiler for complicated case result no solution

### In Topic: Relatively prime

28 April 2015 - 08:29 PM

i'd take the bet.

Spoiler for

### In Topic: A Complicated Numbers Problem

27 April 2015 - 01:27 AM

i had an idea of looking at the last three digits of powers of 5 and 3, but for 3 its not very good, its quite a long list. i'd say this problem is close to intractable.

or at least i dont see any good non mass calcuation solution to it for large powers.