A064539 All...are divisible by 3 but why?

[Robert G. Wilson v]

Everyone,

	As satisfying to me is putting it into a nice Mathematica program. So in essence 
I have supplied the formula.

Bob.

Ralf Stephan wrote:

> Zak,
> for the primes are primes in all bases, the primes are not 'base'.
> But if you have the sequence 'sum of digits is prime' then one must
> know the base of the digits (usually 10) so that would be 'base'.
> So whenever you do something with digits please add 'base'. 
> 
> Why 'base' sequences are uninteresting, I can give you one reason:
> we like to find formulas for and interconnections between sequences, 
> it's a real sport here. The problem: most 'base' sequences don't have
> these or they are really simple, like 10^n-1 for all-nines or so.
> But to get the difficult ones, it is better to study base-2 sequences
> first because they are easier to tackle than base-10. So, 'base-10' is 
> either too easy or too difficult so most of us dismiss them altogether.
> 
> I mean, what can be more satisfying than putting an %F line... ahm a
> formula on a previously untouched sequence?
> 
> 
> ralf
>