A381668 Ternary modular Gray code for n written in base 3.

0, 1, 2, 12, 10, 11, 21, 22, 20, 120, 121, 122, 102, 100, 101, 111, 112, 110, 210, 211, 212, 222, 220, 221, 201, 202, 200, 1200, 1201, 1202, 1212, 1210, 1211, 1221, 1222, 1220, 1020, 1021, 1022, 1002, 1000, 1001, 1011, 1012, 1010, 1110, 1111, 1112, 1122, 1120, 1121

Offset: 0

Author

Joshua Chester, Mar 03 2025

Keywords

• nonn
• base
• easy

Comments

Similar to binary Gray code in that a(n) differs from a(n+1) by one digit, including the last number with a given number of digits compared to a(0).

Crossrefs

Cf. A007089, A105530.

Programs

PARI

a(n) = my(v=digits(n, 3)); forstep(i=#v, 2, -1, v[i]=(v[i]-v[i-1])%3); fromdigits(v, 10); \\ (after A105530) - Andrew Howroyd, Mar 03 2025

Formula

a(n) = A007089(A105530(n)).