<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-04-17T15:43:18Z</responseDate><request verb="GetRecord" identifier="oai:www.recercat.cat:10459.1/463315" metadataPrefix="marc">https://recercat.cat/oai/request</request><GetRecord><record><header><identifier>oai:recercat.cat:10459.1/463315</identifier><datestamp>2025-09-15T18:45:19Z</datestamp><setSpec>com_2072_3622</setSpec><setSpec>col_2072_479130</setSpec></header><metadata><record xmlns="http://www.loc.gov/MARC21/slim" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://www.loc.gov/MARC21/slim http://www.loc.gov/standards/marcxml/schema/MARC21slim.xsd">
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      <subfield code="a">Barrière, Lali</subfield>
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      <subfield code="a">Comellas Padró, Francesc</subfield>
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      <subfield code="a">Dalfó, Cristina</subfield>
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      <subfield code="a">Fiol Mora, Miguel Ángel</subfield>
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      <subfield code="c">2008-04-01</subfield>
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      <subfield code="a">In this paper, we study the spectral properties of a family of trees characterized by two main features: they are spanning subgraphs of the hypercube, and their vertices bear a high degree of (connectedness) hierarchy. Such structures are here called binary hypertrees and they can be recursively defined as the so-called hierarchical product of several complete graphs on two vertices.</subfield>
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      <subfield code="a">Research supported by the Ministry of Education and Science (Spain) and the European Regional Development Fund (ERR) under projects MTM2005-08990-C02-01 and TEC2005-03575 and by the Catalan Research Council under project 2005SGR00256.</subfield>
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      <subfield code="a">Graph operation</subfield>
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      <subfield code="a">Hierarchical product</subfield>
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      <subfield code="a">On the spectra of hypertrees</subfield>
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