News

Announcements

Message from the president
Medal presentations
Make a gift to support The ICA!
News of members

Recreations

Palindromic wishes for the new year
by M. Buratti

Conference announcements

CanaDAM 2023
5 -- 8 June 2023, Winnipeg, Manitoba
Number Theory and Combinatorics in Duluth
31 July 2023 -- 4 August 2023, Duluth, Minnesota
RICCOTA2023
3 -- 7 July 2023, Rijeka, Croatia
Slovenian Conference on Graph Theory 2023
18 -- 24 June 2023, Kranjska Gora, Slovenia

Reports

CCGTA 2022
by D. Nikolova
MCCCC 34
by H. Jordon
Polygons, buildings and related geometries
by J.A. Thas
SEICCGTC 53
by F. Hoffman and M. Provost

Obituaries

Dean Gunnar Hoffman (1949 -- 2022)
by S.H. Holliday
Sanpei Kageyama (1945 -- 2022)
by R. Fuji-Hara, M. Jimbo, S. Kuriki, Y. Miao and K. Momihara
Rudolf Anton Mathon (1940 -- 2022)
by L. Moura

Peer reviewed contributions

A proof via Zeilberger's algorithm of Boole's formula for factorials
by J.M. Campbell
A short note on Zeckendorf type numeration systems with negative digits allowed
by P. Hajnal
Global offensive $k$-alliances in digraphs
by D.A. Mojdeh, B. Samadi and I.G. Yero
Matrix approaches to constructions of group divisible designs
by S. Saurabh and K. Sinha
Self-colorings of graphs
by J. Briggs, D. Hoffman, S.H. Holliday and P. Johnson
Vertex-magic trees with $n$ central vertices and $kn$ leaves have bounded order for each $k$ exceeding the square root of $3$
by J. Calzadillas and D. McQuillan