In this case I want to match a predicate — a function whose result is always true or false — against a set of number. As an example, given the numbers from 1 to 10, the predicate would be responsible for verify which ones are even.
Thus, I want to state that the verification finished, despite of there was more numbers to test.
There could have been more number to verify...
or
Could have been more number to verify...
Which one of the above quoted sentences is grammatically correct?
"There could" is the correct one. The correct sentence is then
There could have been more numbers to verify ...
Note the plural of numbers. Not what you asked for, but I can't help but notice it.
As @Daan says, OP can't grammatically remove the word "there" from his construction.
But I think it's an odd way to phrase this particular statement anyway, since obviously there are more numbers that weren't verified [for some reason]. I think it would be more natural to say...
More (or a greater range of) numbers could have been verified...
The rest of the text would probably need to explain why more numbers weren't verified (either because it would be difficult to do so, or the nature of the test is such that if it works for 1-10, it can reasonably be expected to work for all other numbers anyway).
