a(n) is the smallest even number k whose symmetric representation of sigma(k) has maximum width n.

Terms

a(0) =2a(1) =6a(2) =60a(3) =120a(4) =360a(5) =840a(6) =3360a(7) =2520a(8) =5040a(9) =10080a(10) =15120a(11) =32760a(12) =27720a(13) =50400a(14) =98280a(15) =83160a(16) =110880a(17) =138600a(18) =221760a(19) =277200a(20) =332640a(21) =360360a(22) =554400a(23) =960960a(24) =831600a(25) =942480a(26) =720720a(27) =2217600a(28) =1965600a(29) =1441440