Limiting the consecutive occurrence

[Pixel]

Just had another idea for sed, can it also delete lines that have any 6 character alphabet sequence within them?

This is the output I'm now getting...

Code:

AABCDEFG
AABCDEFH
AABCDEFI
AABCDEFJ
AABCDEFK
AABCDEFL

so the 6 characters in an alphabet sequence within these lines would be

Code:

ABCDEF

so all the lines above would get deleted but only if it has 6?

Do you get me?