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PROJECT EULER · #0027

Quadratic Primes

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Euler discovered the remarkable quadratic formula:

n2+n+41

It turns out that the formula will produce 40 primes for the consecutive integer values 0n39. However, when n=40,402+40+41=40(40+1)+41 is divisible by 41, and certainly when n=41,412+41+41 is clearly divisible by 41.

The incredible formula n279n+1601 was discovered, which produces 80 primes for the consecutive values 0n79. The product of the coefficients, 79 and 1601, is 126479.

Considering quadratics of the form:

n2+an+b, where |a|<1000 and |b|1000

where |n| is the modulus/absolute value of n
e.g. |11|=11 and |4|=4

Find the product of the coefficients, a and b, for the quadratic expression that produces the maximum number of primes for consecutive values of n, starting with n=0.

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