cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A261752 Minimum number of knights on an n X n chessboard such that every square is attacked.

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%I A261752 #39 Feb 16 2025 08:33:26
%S A261752 6,7,8,10,14,18,22,25,28,32,36,43,48,54,58,66,70,78,84,91,98,107,112,
%T A261752 123,128,139,146,156,164
%N A261752 Minimum number of knights on an n X n chessboard such that every square is attacked.
%C A261752 Total domination number of n X n knight graph.
%C A261752 Distinct from A006075 since here all squares must be attacked, whereas, in A006075, all squares are either attacked or occupied.
%C A261752 a(34) = 182, a(36) = 202, a(38) = 224. - _Andy Huchala_, Jun 04 2021
%H A261752 Matthew Conroy, <a href="/A261752/a261752.png">Examples of minimum knight arrangements, n = 4 through n = 14</a>
%H A261752 Andy Huchala, <a href="/A261752/a261752.py3.txt">Python program</a>
%H A261752 Giovanni Resta, <a href="/A261752/a261752.pdf">Examples of minimum knight arrangements, from n = 15 to n = 18</a>
%H A261752 Andy Huchala, <a href="/A261752/a261752_1.pdf">Examples of minimum knight arrangements, from n = 25 to n = 34</a>
%H A261752 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/KnightGraph.html">Knight Graph</a>
%H A261752 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TotalDominationNumber.html">Total Domination Number</a>
%e A261752 An example for the 4 X 4 case:
%e A261752   ....
%e A261752   .NNN
%e A261752   .N..
%e A261752   NN..
%e A261752 and for the 5 x 5 case:
%e A261752   .....
%e A261752   ..N..
%e A261752   .NN..
%e A261752   NNN..
%e A261752   N....
%Y A261752 Cf. A006075.
%K A261752 nonn,more
%O A261752 4,1
%A A261752 _Matthew Conroy_, Aug 31 2015
%E A261752 a(15)-a(18) from _Giovanni Resta_, Aug 31 2015
%E A261752 a(19)-a(26) from _Andy Huchala_, Oct 16 2017
%E A261752 a(27)-a(30) from _Andy Huchala_, Oct 18 2017
%E A261752 a(31)-a(32) from _Andy Huchala_, Jun 04 2021