22221: Near Repdigit 22..221

First few terms (base 10): \[[2^*1_4]_n=\{1,9,41,169,681,\ldots\}\]

First few terms (base 4): \[\{\text{1},\text{21},\text{221},\text{2221},\text{22221},\ldots\}\]

General Formula:\[[2^*1_4]_n={8\cdot4^{n}-5\over3}\]

Equivalent Patterns: (none)

Table

No table data.