A005408 - Odd Numbers

A000010 - Totients

A007318 - Pascal's Triange

And, now that I have published my first sequence to OEIS:

A224502 - Prime numbers that are Palindromes in Balanced Ternary Notation

For example:

`For n=5, a(5)=61 and in balanced ternary notation is 1ī1ī1.`