3906249domain: NAppears in sequencesa(n) = 2*5^n-1.at n=9A081655a(3n) = 3a(3n-1)-3a(3n-2)+2a(3n-3), a(3n+1) = 3a(3n)-3a(3n-1)+2a(3n-2), a(3n+2) = 3a(3n+1)-3a(3n), a(0) = 0, a(1) = 1, a(2) = 2.at n=30A131761Numbers of the form i*5^j-1 (i=1..4, j >= 0).at n=37A181287