a(n) is the least number k such that the sequence of elements of the abundancy index of k is palindromic with length n, or -1 if no such k exists.
A349689
a(n) is the least number k such that the sequence of elements of the abundancy index of k is palindromic with length n, or -1 if no such k exists.
Terms
- a(0) =1a(1) =24a(2) =30a(3) =90a(4) =96a(5) =342a(6) =744a(7) =812160a(8) =330a(9) =147258a(10) =32784a(11) =3314062080a(12) =25896a(13) =565632a(14) =116412a(15) =210317184a(16) =145176a(17) =6182491392a(18) =963108
External references
- oeis: A349689