2 updated test cases
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JavaScript (ES6), 26 bytes

Returns the \$n\$th term, 1-indexed.

f=n=>n--&&[f(n/6|0)]+6-n%6

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JavaScript (ES6), 26 bytes

f=n=>n--&&[f(n/6|0)]+6-n%6

Try it online!

JavaScript (ES6), 26 bytes

Returns the \$n\$th term, 1-indexed.

f=n=>n--&&[f(n/6|0)]+6-n%6

Try it online!

1
source | link

JavaScript (ES6), 26 bytes

f=n=>n--&&[f(n/6|0)]+6-n%6

Try it online!