581334062442domain: NAppears in sequencesFirst differences of 7^n (A000420).at n=14A055272Number of palindromes of length n (in base 7).at n=26A117859Number of palindromes of length n (in base 7).at n=27A117859a(n) = n^(2*n) - n^(2*n - 1).at n=6A259926