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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.

A132445 Number of n X n crossword puzzles with rotational symmetry and at most one black square per row.

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%I A132445 #4 Nov 11 2010 07:34:06
%S A132445 1,3,5,7,16,47,135,643
%N A132445 Number of n X n crossword puzzles with rotational symmetry and at most one black square per row.
%C A132445 Acceptable crossword puzzles must have all words of length 3 or more, at least one word in each row and each column and be connected.
%H A132445 Marc Brodie, <a href="/A132445/a132445.txt">Mathematica program</a>
%e A132445 a(5) = 5 because the only acceptable 5 X 5 crossword puzzles are (using 1's for black squares and 0's for white) are:
%e A132445 00000 10000 10000 00001 00001
%e A132445 00000 00000 10000 00000 00001
%e A132445 00000 00000 00000 00000 00000
%e A132445 00000 00000 00001 00000 10000
%e A132445 00000 00001 00001 10000 10000
%Y A132445 Cf. A130578, A132443, A132444, A132446.
%K A132445 nonn
%O A132445 3,2
%A A132445 Marc Brodie (mbrodie(AT)wju.edu), Aug 21 2007