A255708 No three points (i,a(i)), (j,a(j)), (k,a(k)) are collinear, 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.

0, 0, 1, 1, -1, -1, 4, 2, 2, -3, -5, -2, -7, -2, 5, 3, 3, -5, -4, -4, 6, 5, -6, -3, -10, 11, -6, 4, 18, 11, 19, 7, 12, 12, 6, -13, 19, 7, -10, -7, -9, -14, 13, 23, -28, -8, -14, 9, 8, -22, -9, -8, 23, -11, 15, 22, 13, 8, -21, -13, -26, 9, -12, -12, -11, 40, 21

Offset

0,7

Links

Alois P. Heinz, Table of n, a(n) for n = 0..20000

Maple

a:= proc(n) option remember; local i, j, k, t, ok;
      for t from 0 do for k in [t, -t] do ok:=true;
        for j from n-1 to 1 by -1 while ok do
          for i from j-1 to 0 by -1 while ok do
            ok:= (n-j)*(a(j)-a(i))<>(j-i)*(k-a(j))
        od od; if ok then return k fi
      od od
    end:
seq(a(n), n=0..60);

Crossrefs

Cf. A005836, A179040, A231334, A236266, A236335, A255709.

Sequence in context: A355849 A140395 A061505 * A197154 A275745 A053879

Adjacent sequences: A255705 A255706 A255707 * A255709 A255710 A255711

Keyword

sign,look

Author

Alois P. Heinz, Mar 03 2015

Status

approved