A371951 a(n) is the least number whose aliquot sequence begins with exactly n weird numbers (A006037), or -1 if no such numbers exists.

1, 70, 97930, 597730, 77420770, 459940810, 11835050710

Offset

0,2

Comments

a(7) > 10^11, if it exists.

Links

Table of n, a(n) for n=0..6.

Wikipedia, Aliquot sequence.

Wikipedia, Weird number.

Example

The iterations of A001065 over the terms a(1)..a(6):
  n |        a(n) | Iterations
  --+-------------+--------------------------------------------------------------
  1 |          70 | 70
  2 |       97930 | 97930 -> 103670
  3 |      597730 | 597730 -> 632030 -> 668290
  4 |    77420770 | 77420770 -> 82246430 -> 86946370 -> 92477630
  5 |   459940810 | 459940810 -> 487175990 -> 515884810 -> 546184310 -> 582130570
  6 | 11835050710 | 11835050710 -> 12515648810 -> 13235404630 -> 13991713610
    |             |   -> 14797250230 -> 15649107530

Crossrefs

Cf. A001065, A006037, A371950.

Sequence in context: A172555 A367532 A263590 * A172659 A172759 A172829

Adjacent sequences: A371948 A371949 A371950 * A371952 A371953 A371954

Keyword

nonn,hard,more

Author

Amiram Eldar, Apr 14 2024

Status

approved