a(n) is the number of numbers m such that the number of iterations of r -> r - (largest divisor d < r) needed to reach 1 starting at r = m is equal to n.
A175125
a(n) is the number of numbers m such that the number of iterations of r -> r - (largest divisor d < r) needed to reach 1 starting at r = m is equal to n.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =9a(6) =13a(7) =23a(8) =36a(9) =65a(10) =100a(11) =175a(12) =275a(13) =468a(14) =760a(15) =1266a(16) =2077a(17) =3454a(18) =5690a(19) =9449a(20) =15547a(21) =25709a(22) =42459a(23) =70181a(24) =115947a(25) =191509a(26) =316570a(27) =523087a(28) =864406a(29) =1428174
External references
- oeis: A175125