Mirka Miller's Combinatorics Webinar Series - Revision history

Cristina2: /* Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia) */

2026-09-17T12:43:01Z

‎Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia)

Cristina2: /* Previous Talks */

2026-09-17T12:41:55Z

‎Previous Talks

Cristina2: /* Upcoming Talks: */

2026-09-17T12:37:40Z

‎Upcoming Talks:

Mabreu: /* Upcoming Talks: */

2026-09-16T08:31:06Z

‎Upcoming Talks:

Mabreu at 09:40, 14 September 2026

2026-09-14T09:40:09Z

Mabreu at 09:37, 14 September 2026

2026-09-14T09:37:55Z

Mabreu at 09:36, 14 September 2026

2026-09-14T09:36:18Z

Mabreu at 09:33, 14 September 2026

2026-09-14T09:33:44Z

Mabreu at 14:12, 15 July 2026

2026-07-15T14:12:02Z

Mabreu at 10:05, 11 June 2026

2026-06-11T10:05:46Z

@@ Line 25: / Line 25: @@
 ===Talk 55: Chordal graphs and generalizations - Mónica REYES===
@@ Line 52: / Line 50: @@
 ---
 ===Talk 54: Biregular Cages - György KISS===

← Older revision		Revision as of 12:41, 17 September 2026
Line 22:		Line 22:

	==Previous Talks==		==Previous Talks==
		+
		+	===Talk 55: Chordal graphs and generalizations - Mónica REYES===
		+
		+
		+	=== <big> '''Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia)'''</big> ===
		+
		+
		+	'''Date:''' September 16, 2026'''
		+
		+	'''Time''' 17:00 (CET)
		+
		+	''' Speaker: Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia) '''
		+
		+	''' Title: On Chordal Ring, Multi-ring and Mixed Graphs, and Three-Quarters Circulant Digraphs'''
		+
		+	'''Abstract: ''' Chordal ring graphs are a well-known family of graphs used to model interconnection networks. In this talk, we consider two families of graph and digraph structures related to circulant networks.
		+	First, we study chordal multi-ring, chordal ring mixed, and chordal multi-ring mixed graphs, which generalize the classical chordal ring graphs. Using plane tessellations, we obtain the maximum number of vertices for a given diameter. We also study these graphs as lift graphs over Abelian groups and obtain closed formulas for their spectra.
		+
		+	We then introduce a new family of three-quarters circulant digraphs associated with the cyclic group (\mathbb{Z}_N). Restricting the admissible combinations of two generators to three coordinate sectors gives a new distance-like function. The same geometric approach based on tessellations allows us to obtain Moore-type upper bounds for the order/diameter problem and construct infinite families with prescribed diameter. We give constructions for both even and odd diameters and discuss the maximum possible order.
		+
		+	Join work with Cristina Dalfó and Miquel Àngel Fiol
		+
		+	'''Video:''' [https://drive.google.com/file/d/1r8CL2X5RYdzUvbxxBoXxKVPpCPM2zEjD/view?usp=drive_link https://drive.google.com/file/d/1r8CL2X5RYdzUvbxxBoXxKVPpCPM2zEjD/view?usp=drive_link]
		+
		+	'''Slides:''' [https://drive.google.com/file/d/1eKVRqY7Up3sb4bOS3yVL2ZJxpNBjFX6r/view?usp=drive_link https://drive.google.com/file/d/1eKVRqY7Up3sb4bOS3yVL2ZJxpNBjFX6r/view?usp=drive_link]
		+
		+	'''Link:''' [https://teams.microsoft.com/l/meetup-join/19%3ameeting_NWM1ZTFhY2MtN2U1MS00ODg2LTgyZmItZTQwNmRmMTI4ODA2%40thread.v2/0?context=%7b%22Tid%22%3a%22fe8d7662-ab03-44d3-8787-fd718b76b5dd%22%2c%22Oid%22%3a%222b443e8c-3de6-43e0-87dc-970e1b830292%22%7d https://teams.microsoft.com/l/meetup-join/19%3ameeting_NWM1ZTFhY2MtN2U1MS00ODg2LTgyZmItZTQwNmRmMTI4ODA2%40thread.v2/0?context=%7b%22Tid%22%3a%22fe8d7662-ab03-44d3-8787-fd718b76b5dd%22%2c%22Oid%22%3a%222b443e8c-3de6-43e0-87dc-970e1b830292%22%7d]
		+
		+
		+	---
		+

← Older revision		Revision as of 12:37, 17 September 2026
Line 17:		Line 17:


−	~~=== <big> '''Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia)'''</big> ===~~
−
−
−
−
−	~~'''Date:''' September 16, 2026'''~~
−
−	~~'''Time''' 17:00 (CET)~~
−
−	~~''' Speaker: Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia) '''~~
−
−	~~''' Title: On Chordal Ring, Multi-ring and Mixed Graphs, and Three-Quarters Circulant Digraphs'''~~
−
−	'''Abstract: ''' Chordal ring graphs are a well-known family of graphs used to model interconnection networks. In this talk, we consider two families of graph and digraph structures related to circulant networks.
−	First, we study chordal multi-ring, chordal ring mixed, and chordal multi-ring mixed graphs, which generalize the classical chordal ring graphs. Using plane tessellations, we obtain the maximum number of vertices for a given diameter. We also study these graphs as lift graphs over Abelian groups and obtain closed formulas for their spectra.
−
−	We then introduce a new family of three-quarters circulant digraphs associated with the cyclic group (\mathbb{Z}_N). Restricting the admissible combinations of two generators to three coordinate sectors gives a new distance-like function. The same geometric approach based on tessellations allows us to obtain Moore-type upper bounds for the order/diameter problem and construct infinite families with prescribed diameter. We give constructions for both even and odd diameters and discuss the maximum possible order.
−
−	~~Join work with Cristina Dalfó and Miquel Àngel Fiol~~
−
−
−
−	'''Link:''' [https://teams.microsoft.com/l/meetup-join/19%3ameeting_NWM1ZTFhY2MtN2U1MS00ODg2LTgyZmItZTQwNmRmMTI4ODA2%40thread.v2/0?context=%7b%22Tid%22%3a%22fe8d7662-ab03-44d3-8787-fd718b76b5dd%22%2c%22Oid%22%3a%222b443e8c-3de6-43e0-87dc-970e1b830292%22%7d https://teams.microsoft.com/l/meetup-join/19%3ameeting_NWM1ZTFhY2MtN2U1MS00ODg2LTgyZmItZTQwNmRmMTI4ODA2%40thread.v2/0?context=%7b%22Tid%22%3a%22fe8d7662-ab03-44d3-8787-fd718b76b5dd%22%2c%22Oid%22%3a%222b443e8c-3de6-43e0-87dc-970e1b830292%22%7d]

@@ Line 24: / Line 24: @@
 '''Date:''' September 16, 2026'''
-'''Time''' 18:00 (CET)
+'''Time''' 17:00 (CET)
 ''' Speaker: Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia) '''

← Older revision		Revision as of 09:40, 14 September 2026
Line 9:		Line 9:
	ID de reunión: 897 2536 7001 (for the next talk on May 20, 2026)-->		ID de reunión: 897 2536 7001 (for the next talk on May 20, 2026)-->

−	'''Meeting link:''' ~~[http://meet.google.com/fcf-chxj-dvd http://meet.google.com/fcf-chxj-dvd] (ONLY FOR THE NEXT TALK on June 17, 2026)~~	+	'''Meeting link:''' See below under '''Upcoming Talks'''

@@ Line 496: / Line 496: @@
-=== Talk 35: Ruy Fabila Monroy (Math Department, CINVESTAV, México)  ===
+=== Talk 35: Graphs with non-induced automorphisms of its token graph - Ruy Fabila Monroy (Math Department, CINVESTAV, México)  ===
@@ Line 521: / Line 521: @@
-=== Talk 34: Francesca Merola (Roma Tre University, Italy)  ===
+=== Talk 34: Banff designs: difference methods for coloring incidence graphs -  Francesca Merola (Roma Tre University, Italy)  ===
@@ Line 543: / Line 543: @@
-=== Talk 33: James Tuite (Open University, UK)  ===
+=== Talk 33: Visibility in Graphs - James Tuite (Open University, UK)  ===

@@ Line 274: / Line 274: @@
-===Talk 45: Alexander Gavrilyuk (University of Memphis) ===
+===Talk 45: Non-existence of some Moore Cayley digraphs - Alexander Gavrilyuk (University of Memphis) ===
 '''Date: Wednesday, September 24, 2025'''
@@ Line 299: / Line 299: @@
-=== Talk 44: Federico Romaniello (UNIBAS - Italy) ===
+=== Talk 44: Hamiltonian cycles and perfect matchings: exploring special properties in cubic graphs - Federico Romaniello (UNIBAS - Italy) ===
 '''Date: Wednesday, June 18, 2025'''
@@ Line 322: / Line 322: @@
-=== Talk 43: Isabel Hubard (UNAM - Mexico) ===
+=== Talk 43: Graphs and Groups for Constructing Abstract Polytopes - Isabel Hubard (UNAM - Mexico) ===
 '''Date: Wednesday, May 21, 2025'''
@@ Line 345: / Line 345: @@
-=== Talk 42: Kolja Knauer (Universitat de Barcelona) ===
+=== Talk 42: Coloring Minimal Cayley Graphs - Kolja Knauer (Universitat de Barcelona) ===
 '''Date: Wednesday, April 16, 2025'''
@@ Line 368: / Line 368: @@
-=== Talk 41: Adriana Hansberg (UNAM - Mexico) ===
+=== Talk 41: Graphs with constant link and induced Turán numbers - Adriana Hansberg (UNAM - Mexico) ===
 '''Date: Wednesday March 19, 2025'''

@@ Line 17: / Line 17: @@
-=== <big> '''György KISS  (Eötvös Loránd University) - Biregular Cages'''</big> ===
+=== <big> '''Mónica A. Reyes (Universitat de Lleida, Igualada (Barcelona), Catalonia)'''</big> ===
-'''Date:''' Originally programmed for May 20, 2026 for technical issues it was rescheduled for '''July 15, 2026'''
 '''Time''' 17:00 (CET)
@@ Line 41: / Line 71: @@
 ----
 ===Talk 53: Graphs with bounded diameter/girth ratio - Štefania Glevická===

@@ Line 16: / Line 16: @@
 === <big> '''György KISS  (Eötvös Loránd University) - Biregular Cages'''</big> ===
@@ Line 72: / Line 50: @@
 ==Previous Talks==
 ===Talk 52: Tverberg type results: The study of partitions of points, simplicial complexes, geometry, and beyond - Déborah OLIVEROS BRANIFF===

← Older revision		Revision as of 10:05, 11 June 2026
Line 16:		Line 16:


−	=== <big> '''Štefania Glevická (Comenius University, Bratislava, Slovakia)	+	=== <big> '''Štefania Glevická (Comenius University, Bratislava, Slovakia) - Graphs with bounded diameter/girth ratio'''</big> ===
−	- Graphs with bounded diameter/girth ratio'''</big> ===