11311: Near Repdigit Palindrome 11..11311..11

First few terms (base 10): \[[1^*31^*_5]_n=\{3,41,831,19781,489531,\ldots\}\]

First few terms (base 5): \[\{\text{3},\text{131},\text{11311},\text{1113111},\text{111131111},\ldots\}\]

General Formula:\[[1^*31^*_5]_n={5\cdot5^{2n}+8\cdot5^{n}-1\over4}\]

Equivalent Patterns: (none)

Table

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