112020domain: NAppears in sequences3-smooth numbers in ternary representation.at n=30A131096Number of permutations of 2 copies of 1..n avoiding adjacent step pattern up, down, down, up, up, up.at n=4A177582Digitally balanced numbers: ternary numbers which have the same number of 0's as 1's as 2's.at n=20A181986