120140domain: NAppears in sequencesPositive numbers k such that k and 3*k are anagrams in base 5 (written in base 5).at n=31A023062Expansion of Product_{k>=1} ((1 + k*x^k) / (1 - x^k))^k.at n=12A268502a(n) = Sum_{i+j+k=n, i,j,k >= 1} sigma(i) * sigma(j) * sigma(k).at n=20A374951