Quadratic reciprocity via generalized Fibonacci numbers?



This is a pet idea of mine which I thought I'd share. Fix a prime q congruent to 1mod4 and define a sequence Fn by F0=0,F1=1, and
Fn+2=Fn+1+q14Fn.

Then Fn=αnβnαβ where α,β are the two roots of f(x)=x2xq14. When q=5 we recover the ordinary Fibonacci numbers. The discriminant of f(x) is q, so it splits modp if and only if q is a quadratic residue modp.
If (qp)=1, then the Frobenius morphism xxp swaps α and β (working over Fp), hence Fp1modp. And if (qp)=1, then the Frobenius morphism fixes α and β, hence Fp1modp. In other words,
Fp(qp)modp.
Quadratic reciprocity in this case is equivalent to the statement that
Fp(pq)modp.
Question: Does anyone have any ideas about how to prove this directly, thereby proving quadratic reciprocity in the case that q1mod4?
My pet approach is to think of Fp as counting the number of ways to tile a row of length p1 by tiles of size 1 and 2, where there is one type of tile of size 1 and q14 types of tiles of size 2. The problem is that I don't see, say, an obvious action of the cyclic group Z/pZ on this set. Any ideas?


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