Optimal Rational Approximations by the Modified Fourier Basis

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are the roots of <span class="nowrap"><svg height="18.5113pt" id="M424" style="vertical-align:-5.150499pt" version="1.1" viewbox="-0.0498162 -13.3608 49.7131 18.5113" width="49.7131pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M541 160L512 170C485 116 462 88 439 67C411 41 376 35 318 35C272 35 238 37 224 48C207 61 205 85 212 121L290 533C305 611 308 615 391 622L397 650H139L133 622C217 615 221 612 206 533L126 118C111 41 103 34 23 26L17 0H474C489 31 528 124 541 160Z" id="g113-77"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.185,-6.844)"><path d="M309 -142C211 -61 151 99 151 271S210 601 309 683L288 710C141 611 75 451 75 272V271C75 90 141 -72 288 -169L309 -142Z" id="g50-41"></path></g><g transform="matrix(.0091,0,0,-0.0091,10.443,-6.844)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 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Abstract and Applied Analysis

Optimal Rational Approximations by the Modified Fourier Basis

Figure 4