0,2

Table of n, a(n) for n=0..7.

The sets of numbers obtainable at the n-th step are:

S(0) = { 1 },

S(1) = { 0, 1, 2 },

S(2) = { -1, 0, 1/2, 1, 2, 3, 4 },

S(3) = { -3, -2, -3/2, -1, -1/2, 0, 1/4, 1/3, 1/2, 2/3, 1, 3/2, 2, 5/2, 3, 4, 5, 6, 8, 9, 16 }.

Cf. A214872, A288759, A288850.

A216999 provides the corresponding results if division is not used.

Sequence in context: A319123 A173794 A049365 * A031885 A259202 A169981

Adjacent sequences: A288846 A288847 A288848 * A288850 A288851 A288852

nonn,hard,more

Hugo Pfoertner, Jun 18 2017

a(7) from Alois P. Heinz, Jun 18 2017

approved