loop-detection-looks-at-ranges-too.dfy(11,17): Warning: Selected triggers: {P(x)} (may loop with {P(x + 1)})
 (!) Suppressing loops would leave this expression without triggers.
loop-detection-looks-at-ranges-too.dfy(13,17): Warning: Selected triggers: {P(x)} (may loop with {P(x + 1)})
 (!) Suppressing loops would leave this expression without triggers.

Dafny program verifier finished with 3 verified, 0 errors