On two applications of polynomials x^k-cx-d over finite fields and more

For integers k∈[2,q−2] coprime to q−1 , we first bound the number of zeroes of the family of polynomials xk−cx−d∈Fq[x] where q=2n such that q−1 is a prime or q=3n such that (q−1)/2 is a prime. This gives us bounds on cross-correlation of a subfamily of Golomb Costas arrays. Next, we show that the zero set of xk−cx−d over Fq is a planar almost difference set in F∗q and hence for some set of pairs (c, d), they produce optical orthogonal codes with λ=1 . More generally, we give an algorithm to produce optical orthogonal codes (OOCs) from P(x)=xℓ1+cℓ2xℓ2+cℓ2−1xℓ2−1+⋯+c1x∈Fq[x] where interestingly ℓ1≫ℓ2 . We focus on the case ℓ2∈{2,3} and provide examples of (q−1,w,λ) -OOCs with λ∈{2,3} .


Value sets of folding polynomials over finite fields
Küçüksakallı, Ömer (2019-01-01)
Let k be a positive integer that is relatively prime to the order of the Weyl group of a semisimple complex Lie algebra g. We find the cardinality of the value sets of the folding polynomials P-g(k)(x) is an element of Z[x] of arbitrary rank n >= 1, over finite fields. We achieve this by using a characterization of their fixed points in terms of exponential sums.
On the Occurrence of Perfect Squares Among Values of Certain Polynomial Products
Gurel, Erhan (2016-06-01)
We prove that the product of first n consecutive values of the polynomial P(k) = 4k(4) + 1 is a perfect square infinitely often whereas the product of first n consecutive values of the polynomial Q(k) = k(4) + 4 is a perfect square only for n = 2.
On algebraic K-theory of real algebraic varieties with circle action
Ozan, Yıldıray (Elsevier BV, 2002-05-24)
Assume that X is a compact connected orientable nonsingular real algebraic variety with an algebraic free S-1-action so that the quotient Y=X/S-1 is also a real algebraic variety. If pi:X --> Y is the quotient map then the induced map between reduced algebraic K-groups, tensored with Q, pi* : (K) over bar (0)(R(Y, C)) circle times Q --> (K) over bar (0)(R(X, C)) circle times Q is onto, where R(X, C) = R(X) circle times C, R(X) denoting the ring of entire rational (regular) functions on the real algebraic va...
On a Fitting length conjecture without the coprimeness condition
Ercan, Gülin (Springer Science and Business Media LLC, 2012-08-01)
Let A be a finite nilpotent group acting fixed point freely by automorphisms on the finite solvable group G. It is conjectured that the Fitting length of G is bounded by the number of primes dividing the order of A, counted with multiplicities. The main result of this paper shows that the conjecture is true in the case where A is cyclic of order p (n) q, for prime numbers p and q coprime to 6 and G has abelian Sylow 2-subgroups.
On the Polynomial Multiplication in Chebyshev Form
Akleylek, Sedat; Cenk, Murat; Özbudak, Ferruh (2012-04-01)
We give an efficient multiplication method for polynomials in Chebyshev form. This multiplication method is different from the previous ones. Theoretically, we show that the number of multiplications is at least as good as Karatsuba-based algorithm. Moreover, using the proposed method, we improve the number of additions slightly. We remark that our method works efficiently for any N and it is easy to implement. To the best of our knowledge, the proposed method has the best multiplication and addition comple...
Citation Formats
C. İrimağzı and F. Özbudak, On two applications of polynomials x^k-cx-d over finite fields and more. 2023.