a(1)=2^3*5*7*29=8120; for n>1, a(n) = (-1)sigma(a(n-1)).

Terms

a(0) =8120a(1) =8736a(2) =8784a(3) =19140a(4) =11200a(5) =21750a(6) =8624a(7) =15950a(8) =8120a(9) =8736a(10) =8784a(11) =19140a(12) =11200a(13) =21750a(14) =8624a(15) =15950a(16) =8120a(17) =8736a(18) =8784a(19) =19140a(20) =11200a(21) =21750a(22) =8624a(23) =15950a(24) =8120a(25) =8736a(26) =8784a(27) =19140a(28) =11200a(29) =21750