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A255709 No three points (i,a(i)), (j,a(j)), (k,a(k)) are collinear and all values distinct, for n = 0,1,2,... the value of a(n) is chosen to be m or -m (in this order) for the smallest m>=0 satisfying the condition.

%I A255709 #11 Jul 10 2019 01:48:19
%S A255709 0,1,-1,2,3,-2,-5,-3,4,-6,6,-7,-4,5,12,16,7,8,-10,-8,9,19,14,-12,-14,
%T A255709 -9,21,10,-11,-15,17,15,-19,13,-22,-13,-16,-24,11,18,22,-18,25,23,-17,
%U A255709 24,40,-21,-38,20,-29,36,-30,-20,32,-34,26,43,-23,37,-26,33
%N A255709 No three points (i,a(i)), (j,a(j)), (k,a(k)) are collinear and all values distinct, for n = 0,1,2,... the value of a(n) is chosen to be m or -m (in this order) for the smallest m>=0 satisfying the condition.
%H A255709 Alois P. Heinz, <a href="/A255709/b255709.txt">Table of n, a(n) for n = 0..20000</a>
%p A255709 b:= proc() true end:
%p A255709 a:= proc(n) option remember; local i, j, k, t, ok;
%p A255709       for t from 0 do for k in [t, -t] do ok:=b(k);
%p A255709         for j from n-1 to 1 by -1 while ok do
%p A255709           for i from j-1 to 0 by -1 while ok do
%p A255709             ok:= (n-j)*(a(j)-a(i))<>(j-i)*(k-a(j))
%p A255709         od od; if ok then b(k):=false; return k fi
%p A255709       od od
%p A255709     end:
%p A255709 seq(a(n), n=0..60);
%Y A255709 Cf. A005836, A179040, A231334, A236266, A236335, A255708.
%K A255709 sign,look
%O A255709 0,4
%A A255709 _Alois P. Heinz_, Mar 03 2015