Let $$p_1,p_2,\ldots ,p_n$$ be distinct odd primes and let $$e_1,e_2,\ldots ,e_n$$ be positive integers. Based on cyclotomic classes proposed by Ding and Helleseth (Finite Fields Appl 4:140–166, 1998), a binary cyclotomic sequence of period $$p_1^{e_{1}}p_{2}^{e_{2}}\ldots p_{n}^{e_n}$$ is defined and denoted by $$\underline{s_\Upsilon }$$ . The linear complexity of $$\underline{s_\Upsilon }$$ is determined and is proved to be greater than or equal to $$(p_1^{e_{1}}p_{2}^{e_{2}}\ldots p_{n}^{e_n}-1)/2$$ . The autocorrelation function of $$\underline{s_\Upsilon }$$ is explicitly computed. Let $$\ell \in \{1,2,\ldots ,n\}$$ . We also explicitly compute the crosscorrelation function of $$\underline{s_\Upsilon }$$ and the Legendre sequence $$\underline{L_{p_\ell }}$$ with respect to $$p_\ell $$ . It is shown that $$\underline{s_\Upsilon }$$ and $$\underline{L_{p_\ell }}$$ have two-level or three-level crosscorrelation, and all their two-level crosscorrelation functions are determined.
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