Pub Date : 1989-01-01DOI: 10.1016/1385-7258(89)90004-8
P.D.T.A. Elliott
It is shown that certain commonly occurring conditions may be factored out of sums of multiplicative arithmetic functions.
A function is arithmetic if it is defined on the positive integers. Those complex-valued arithmetic functions g which satisfy the relation g(ab) = g(a)g(b) for all coprime pairs of positive integers a, b are here called multiplicative. In this paper g will be a multiplicative function which satisfies |g(n)| ≤ 1 for all positive integers n.
{"title":"Extrapolating the mean-values of multiplicative functions","authors":"P.D.T.A. Elliott","doi":"10.1016/1385-7258(89)90004-8","DOIUrl":"10.1016/1385-7258(89)90004-8","url":null,"abstract":"<div><p>It is shown that certain commonly occurring conditions may be factored out of sums of multiplicative arithmetic functions.</p><p>A function is <em>arithmetic</em> if it is defined on the positive integers. Those complex-valued arithmetic functions g which satisfy the relation <em>g</em>(<em>ab</em>) = <em>g</em>(<em>a</em>)<em>g</em>(<em>b</em>) for all coprime pairs of positive integers a, b are here called <em>multiplicative</em>. In this paper <em>g</em> will be a multiplicative function which satisfies |<em>g</em>(<em>n</em>)| ≤ 1 for all positive integers <em>n</em>.</p></div>","PeriodicalId":100664,"journal":{"name":"Indagationes Mathematicae (Proceedings)","volume":"92 4","pages":"Pages 409-420"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/1385-7258(89)90004-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"93777321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1989-01-01DOI: 10.1016/1385-7258(89)90002-4
Eva Bayer-Fluckiger
Every Galois extension of odd degree has a self-dual normal basis.
每一个奇次的伽罗瓦扩展都有一个自对偶正规基。
{"title":"Self-dual normal bases","authors":"Eva Bayer-Fluckiger","doi":"10.1016/1385-7258(89)90002-4","DOIUrl":"https://doi.org/10.1016/1385-7258(89)90002-4","url":null,"abstract":"<div><p>Every Galois extension of odd degree has a self-dual normal basis.</p></div>","PeriodicalId":100664,"journal":{"name":"Indagationes Mathematicae (Proceedings)","volume":"92 4","pages":"Pages 379-383"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/1385-7258(89)90002-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92121409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1989-01-01DOI: 10.1016/1385-7258(89)90009-7
I.J. Maddox
For all positive a the point spectrum of the (C, α) matrix is determined, where the matrix is regarded as an operator on certain Banach sequence spaces. In particular the point spectrum is obtained in the spaces Ip(X), with 1<p≤∞, where X is a Banach space.
{"title":"Point spectra of Cesàro matrices","authors":"I.J. Maddox","doi":"10.1016/1385-7258(89)90009-7","DOIUrl":"10.1016/1385-7258(89)90009-7","url":null,"abstract":"<div><p>For all positive a the point spectrum of the (<em>C</em>, α) matrix is determined, where the matrix is regarded as an operator on certain Banach sequence spaces. In particular the point spectrum is obtained in the spaces <em>I</em><sub><em>p</em></sub>(<em>X</em>), with 1<<em>p</em>≤∞, where <em>X</em> is a Banach space.</p></div>","PeriodicalId":100664,"journal":{"name":"Indagationes Mathematicae (Proceedings)","volume":"92 4","pages":"Pages 465-470"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/1385-7258(89)90009-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"99062947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1989-01-01DOI: 10.1016/1385-7258(89)90012-7
Jan Stevens
We show that through g + 5 general points of g−1 passes a canonical curve of genus g. For low, odd values of g one may assign more points (g+5+[6/g−2]). The proof is based on a study of the normal bundle of g-cuspidal rational curves.
These facts have consequences for the smoothability of the curve singularity consisting of r lines through the origin of kn, n<r≤(2n+1), in generic position. We strengthen some results of Pinkham and Greuel on such curves.
{"title":"On the number of points determining a canonical curve","authors":"Jan Stevens","doi":"10.1016/1385-7258(89)90012-7","DOIUrl":"10.1016/1385-7258(89)90012-7","url":null,"abstract":"<div><p>We show that through <em>g</em> + 5 general points of <span><math><mtext>P</mtext></math></span><sup><em>g</em>−1</sup> passes a canonical curve of genus g. For low, odd values of g one may assign more points (<em>g</em>+5+[6/<em>g</em>−2]). The proof is based on a study of the normal bundle of <em>g</em>-cuspidal rational curves.</p><p>These facts have consequences for the smoothability of the curve singularity consisting of r lines through the origin of <em>k</em><sup><em>n</em></sup>, <em>n</em><<em>r</em>≤(<sub>2</sub><sup><em>n</em>+1</sup>), in generic position. We strengthen some results of Pinkham and Greuel on such curves.</p></div>","PeriodicalId":100664,"journal":{"name":"Indagationes Mathematicae (Proceedings)","volume":"92 4","pages":"Pages 485-494"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/1385-7258(89)90012-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"108808336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1989-01-01DOI: 10.1016/1385-7258(89)90013-9
Jan Stochel, F.H. Szafraniec
{"title":"The normal part of an unbounded operator","authors":"Jan Stochel, F.H. Szafraniec","doi":"10.1016/1385-7258(89)90013-9","DOIUrl":"10.1016/1385-7258(89)90013-9","url":null,"abstract":"","PeriodicalId":100664,"journal":{"name":"Indagationes Mathematicae (Proceedings)","volume":"92 4","pages":"Pages 495-503"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/1385-7258(89)90013-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"99107832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1989-01-01DOI: 10.1016/1385-7258(89)90007-3
H.T. Koelink , T.H. Koornwinder
The tensor product of two unitary irreducible representations of the quantum group SμU(2) is decomposed in a direct sum of unitary irreducible representations with explicit realizations. The Clebsch-Gordan coefficients yield the orthogonality relations for q-Hahn and dual q-Hahn polynomials.
{"title":"The Clebsch-Gordan coefficients for the quantum group SμU(2) and q-Hahn polynomials","authors":"H.T. Koelink , T.H. Koornwinder","doi":"10.1016/1385-7258(89)90007-3","DOIUrl":"10.1016/1385-7258(89)90007-3","url":null,"abstract":"<div><p>The tensor product of two unitary irreducible representations of the quantum group <em>S</em><sub><em>μ</em></sub><em>U</em>(2) is decomposed in a direct sum of unitary irreducible representations with explicit realizations. The Clebsch-Gordan coefficients yield the orthogonality relations for <em>q</em>-Hahn and dual <em>q</em>-Hahn polynomials.</p></div>","PeriodicalId":100664,"journal":{"name":"Indagationes Mathematicae (Proceedings)","volume":"92 4","pages":"Pages 443-456"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/1385-7258(89)90007-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"106579550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}