APL (Dyalog Unicode), 22 17 bytes

∊({⍵+⍳≢⍵}¨+\∘≠⊆⊢)

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Monadic ≠ doesn't work on TIO because it's got an older version of Dyalog APL, so I've defined a function U to stand in for that.

Another solution with ≠, 20 bytes

{⍵+(⊣×1+⊢)/∘⌽¨,\~≠⍵}

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APL (Dyalog Unicode), 22 17 10 bytes

Saved 7 bytes thanks to ovs!

∊{⊂⍺+⍳≢⍵}⌸

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APL (Dyalog Unicode), 22 17 bytes

∊({⍵+⍳≢⍵}¨+\∘≠⊆⊢)

Try it online!

Monadic ≠ doesn't work on TIO because it's got an older version of Dyalog APL, so I've defined a function U to stand in for that.

APL (Dyalog Unicode), 22 17 bytes

∊({⍵+⍳≢⍵}¨+\∘≠⊆⊢)

Try it online!

Monadic ≠ doesn't work on TIO because it's got an older version of Dyalog APL, so I've defined a function U to stand in for that.

Another solution with ≠, 20 bytes

{⍵+(⊣×1+⊢)/∘⌽¨,\~≠⍵}

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APL (Dyalog Unicode), 22 bytes

∊({⍵+⍳≢⍵}¨⊢⊆⍨⊢+1+∘|⌊/)

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I was hoping for an extremely short answer using ⊆, but it doesn't allow negative numbers (on the left). Explanation coming.

APL (Dyalog Unicode), 17 bytes

∊({⍵+⍳≢⍵}¨+\∘≠⊆⊢)

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Doesn't work on TIO

APL (Dyalog Unicode), 22 17 bytes

∊({⍵+⍳≢⍵}¨+\∘≠⊆⊢)

Try it online!

Monadic ≠ doesn't work on TIO because it's got an older version of Dyalog APL, so I've defined a function U to stand in for that.