Proving the Validity of 5y^2 + 5y + 1 in Prime Numbers

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The discussion revolves around proving whether the expression 5y^2 + 5y + 1 yields prime numbers for all integers y greater than or equal to 1. Participants express uncertainty about how to approach the proof and suggest testing various values, including larger integers, to gather evidence. A hint is provided to use a Visual Basic script to check divisibility by specific primes, such as 11 and 19, indicating that the expression may not always yield prime results. The conversation highlights the need for a clearer statement regarding the conditions under which the expression can be evaluated as prime. Overall, the validity of the expression in producing prime numbers remains unproven.
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prove if the statement is true, else form it's negation and prove that is true:

## \forall y \in (x | x \in \mathbb Z , x \geq 1), 5y^2 + 5y + 1 ##

I think it's true, but I can't really even get started to prove it

I really suck at these and need help please, thank you!
 
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There is no statement that could be evaluated as true or false.
It is like "prove that this is true or false: 5".

I guess there is "is prime" missing. Did you test some numbers to check it? Don't just check small numbers, consider larger numbers as well.


Big hint:
There is no known useful formula to generate an arbitrary number of primes without excessive calculations.
 
Put this text into an *.vbs file and run it:

For y = 1 To 100
z = 5*y*y + 5*y + 1
if (z mod 11)=0 then MsgBox("f(" & y & ") is divisible by 11.")
if (z mod 19)=0 then MsgBox("f(" & y & ") is divisible by 19.")
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Where did "divisible by 5" and "divisible by 11" come from?
 
I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...
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