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Suppose I have the following list :

l={{a, b, d}, {a, v}, {b, c, d}}

I want to delete those elements that contain the letter a such that I get:

Output: {{b, c, d}}

I tried DeleteCases command but it does not work. What I we want two letters such as "a" and "c" In that case the output shall be empty. How one handles this?

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  • $\begingroup$ Also consider Select[l, FreeQ[a]] and Select[l, FreeQ[#, c] && MemberQ[#, v] &] ? $\endgroup$ – user1066 Jul 26 '18 at 21:22
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Pick[l, FreeQ[a]  /@ l]

{{b, c, d}}

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  • $\begingroup$ Thanks, what if you want do to it for two letters like a and b? (in this case we expect an empty list). In other words can FreeQ be over two letters instead of only one? $\endgroup$ – William Jul 26 '18 at 16:17
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    $\begingroup$ @William Replace a by a|b $\endgroup$ – Coolwater Jul 26 '18 at 16:19
  • $\begingroup$ Fabulous thanks $\endgroup$ – William Jul 26 '18 at 16:20

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