Take elliptic curve E: y2 ≡ x3 + 5x + 21 over 23

Reciprocal value table, if needed
x 1 2 3 4 5 6 7 8 9 10
x-1 mod 23 1 12 8 6 14 4 10 3 18 7
x 11 12 13 14 15 16 17 18 19 20
x-1 mod 23 21 2 16 5 20 13 19 9 17 15
x 21
x-1 mod 23 11