OFFSET

1,1

COMMENTS

Each term starts with either 12 or 13. If a term is written as a0a1a2...a2a1a0, then a_i is either 0 or 1 when i is even and a_i is either 2 or 3 when i is odd (see A321210).

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10008

FORMULA

a(n) = (A321210(n)-1)/6.

PROG

CROSSREFS

KEYWORD

nonn,base

AUTHOR

Chai Wah Wu, Dec 05 2019

STATUS

approved