If f[x]=(sum of unitary-proper divisors of x)=A063919[x] is iterated, the iteration may lead to a fixed point which is either 0 or belongs to A002827, a unitary-perfect-number >1: 6,60,90,87360... Sequence gives initial values for which the iteration ends in 87360, the 4th unitary perfect number.
A098186
If f[x]=(sum of unitary-proper divisors of x)=A063919[x] is iterated, the iteration may lead to a fixed point which is either 0 or belongs to A002827, a unitary-perfect-number >1: 6,60,90,87360... Sequence gives initial values for which the iteration ends in 87360, the 4th unitary perfect number.
Terms
- a(0) =87360a(1) =232608a(2) =356640a(3) =465144a(4) =527712a(5) =565728a(6) =713208a(7) =1018248a(8) =1055352a(9) =1211352a(10) =1240032a(11) =1303728a(12) =1316904a(13) =1352568a(14) =1357584a(15) =1360416a(16) =1379280a(17) =1550472a(18) =1690440a(19) =1835592a(20) =2035608a(21) =2078328a(22) =2110632a(23) =2262892a(24) =2422632
External references
- oeis: A098186