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%I #17 Jun 27 2017 05:40:42
%S 1,4,7,14,19,32,39,58,67,92,103,134,147,184,199,242,259,308
%N On an n X n board, a(n) is the maximal number of squares covered by a self-avoiding path made of alternated vertical and horizontal unitary steps.
%C From an idea of _Leroy Quet_, discussed on the SeqFan mailing list.
%C David Wilson conjectures that the formula for a(n) is:
%C a(1)=1, then, a(n)=n^2-n+2 for n even, and a(n)=n^2-2n+4 for n>1 odd.
%H Giovanni Resta, <a href="/A157615/a157615.pdf">Illustration of initial terms</a>
%Y A157616, A157617
%K hard,more,nonn,nice
%O 1,2
%A _Giovanni Resta_, Mar 03 2009
%E a(13)-a(18) computed using integer linear programming by _Rob Pratt_, Apr 07 2015