What key scale is this?

[blarvis]

A, F#, F, A#

[andreslr6]

In what context? by itself it sounds more like a 0145 tetrachord.

If it´s tonal music I can imagining it fitting in B major, because of the A#, but it depends in the context, is it inside a piece? if it is, which piece?

[keypeg]

For all we know, the F# could be Gb and the A# could be Bb. Then it would be
A, Gb, F, Bb
A scale does not use the same letter names twice.

[andreslr6]

For all we know, the F# could be Gb and the A# could be Bb. Then it would be
A, Gb, F, Bb
A scale does not use the same letter names twice.

Not that I agree with what you say, but it does bring out the possibility of it being a harmonic Bb minor scale .

[Bob]

Bitonal?


Some kind of dissonant extended chord?