Very nice write-up and illustration of Bloom filters. Something I didn't get though, is why pick k=27 instead of say k=20, which seems to have similar size, bu

Very nice write-up and illustration of Bloom filters. Something I didn't get though, is why pick k=27 instead of say k=20, which seems to have similar size, but would be faster to query? In fact, varying k between 20 and 30 doesn't seem to have much impact on size, so why not reduce it even further?