Low autocorrelation binary sequences beyond length 66
Find ±1 sequences of length 67 and beyond with lower autocorrelation energy than known, or prove optimality; optima are known only up to 66.
Problems
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Matching problems
Legendre pairs of length 115 and the other open lengths below 200
Find a Legendre pair of length 115, 145, 159, 161, 169, 175, 177, 185, 187 or 195, the open odd lengths below 200.