Alicornutopia

Is the rule just "read the nth letter of the alphabet as the digit n, then if the resulting number is prime, yes, otherwise no" with some extension to letters greater than nine?

Testing:
'edg'
'547'
'abc'
'123'
'z'
'j'
'k'

Pfff. I was getting confused by the fact my list started with a '0' – "but prime numbers don't go 3, 4, 6, 8" :P

Might be that the letters of the alphabet get their position in it (the alphabet) as their value, modulo 10 or something, then you use that as a regular number.

i.e. 'a' gets treated as '1', so 'a0' is like '10', and 'm' is '3' (13 mod 10 = 3), so 'm0' would be '30'. Or something.

Edit: as in, like Moriwen said, but with the 'some extension' being 'modulo 10 of their positional value'.

Right, I was thinking either that or just treating 'j' as '10' (i.e. reading it as two place values instead of one). Hopefully 'k' will distinguish between those two possibilities, because if it's mod 10 it'll be 1 which isn't prime, and if it's just reading it as 11 it is prime.

If we are on the right track, after Pedro’s introduction, I’ll up the planned difficulty of my rule.

MTC wrote:02
03
04
13
15
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
A
BBC
BEE

Numbers: Yes, yes, no, no, no
Letters: No, no, no, yes, no

Throne3d wrote:'00'
'01'
'05'
'10'
'11'
'20'
'21'
'30'
'40'
'50'

No, no, yes, no, yes, yes, yes, yes, no, yes

DanielH wrote:'bb'
'b'
'be'

'BBC'
'BEE'

'11'
'13'
'17'

'10'
'12'

No, repeat yes, yes, repeat yes, repeat no, repeat yes, repeat no, no, repeat no, yes

Moriwen wrote:Is the rule just "read the nth letter of the alphabet as the digit n, then if the resulting number is prime, yes, otherwise no" with some extension to letters greater than nine?

I can't evaluate this guess without knowing what extension you have in mind :P

Moriwen wrote:'edg'
'547'
'abc'
'123'
'z'
'j'
'k'

Only k is yes

Okay, hypothesis: "read the nth letter of the alphabet as the digit-or-string-of-digits n, then if the resulting number is prime, yes, otherwise no." (i.e., "k7" => "117").

Pedro, you said "bb" is a repeat yes, but it's not on the list. Are you sure?

Guess: accepted iff sum of all digits and letters’ positions in the alphabet is prime.

Moriwen wrote:Pedro, you said "bb" is a repeat yes, but it's not on the list. Are you sure?

No I missed the bb, it's a no.

DanielH wrote:Guess: accepted iff sum of all digits and letters’ positions in the alphabet is prime.

Correct! The original text of the rule was:

The sum of the converted values of the characters in the string must be a prime number (converted values being a = 1, b = 2, c = 3, etc, and numbers being themselves).

Which is significantly easier than I'd naively expected it to be, and I have another one that's more difficult but if anyone else wants to start a game here instead go ahead.

Okay, new rule!

Acceptable Koans: strings of accentless English letters of any length
Rule SHA-1 hash: 0a7dd392f13aabecec354deffcff56b0a93c7ce4
Positive example: bbb
Negative example: bee