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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A334144 Consider the mapping k -> (k - (k/p)), where prime p | k. a(n) = maximum distinct terms at any position j among the various paths to 1.

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%I A334144 #23 May 08 2020 23:21:01
%S A334144 1,1,1,1,1,2,2,1,2,2,2,2,2,2,3,1,1,2,2,2,3,2,2,2,2,2,2,3,3,3,3,1,4,2,
%T A334144 4,3,3,3,3,2,2,4,4,3,4,3,3,2,4,2,3,3,3,3,3,3,3,3,3,4,4,4,4,1,5,5,5,2,
%U A334144 5,5,5,3,3,3,4,3,6,4,4,2,3,2,2,4,3,4,4,3,3,5,5,3,5,3,5,2,2,4,6,3,3,3,3,3,6,3
%N A334144 Consider the mapping k -> (k - (k/p)), where prime p | k. a(n) = maximum distinct terms at any position j among the various paths to 1.
%C A334144 Let i = A064097(n) be the common path length and let 1 <= j <= i. Given a path P, we find for any j relatively few distinct values. Regarding a common path length i, see A333123 comment 2, and proof at A064097.
%C A334144 Maximum term in row n of A334184.
%H A334144 Peter Kagey, <a href="/A334144/b334144.txt">Table of n, a(n) for n = 1..10000</a>
%H A334144 Peter Kagey, Math.StackExchange, <a href="https://math.stackexchange.com/questions/3632156/does-a-graded-poset-on-mathbbn-0-generated-from-subtracting-factors-defi">Does a graded poset on the positive integers generated from subtracting factors define a lattice?</a>
%H A334144 Richard Stanley, <a href="https://ocw.mit.edu/courses/mathematics/18-318-topics-in-algebraic-combinatorics-spring-2006/lecture-notes/sperner.pdf">MIT OpenCourseWare, Lecture Notes in Algebraic Combinatorics: The Sperner Property</a>
%H A334144 Wikipedia, <a href="https://en.wikipedia.org/wiki/Sperner_property_of_a_partially_ordered_set">Sperner property of a partially ordered set</a>
%e A334144 For n=15, the paths are shown vertically at left, and the graph obtained appears at right:
%e A334144   15   15   15   15   15  =>         15
%e A334144    |    |    |    |    |            _/ \_
%e A334144    |    |    |    |    |           /     \
%e A334144   10   10   12   12   12  =>     10       12
%e A334144    |    |    |    |    |         | \_   _/ |
%e A334144    |    |    |    |    |         |   \ /   |
%e A334144    5    8    6    6    8  =>     5    8    6
%e A334144    |    |    |    |    |          \_  |  _/|
%e A334144    |    |    |    |    |            \_|_/  |
%e A334144    4    4    3    4    4  =>          4    3
%e A334144    |    |    |    |    |              |  _/
%e A334144    |    |    |    |    |              |_/
%e A334144    2    2    2    2    2  =>          2
%e A334144    |    |    |    |    |              |
%e A334144    |    |    |    |    |              |
%e A334144    1    1    1    1    1  =>          1
%e A334144 Because the maximum number of distinct terms in any row is 3, a(15) = 3.
%t A334144 Max[Length@ Union@ # & /@ Transpose@ #] & /@ Nest[Function[{a, n}, Append[a, Join @@ Table[Flatten@ Prepend[#, n] & /@ a[[n - n/p]], {p, FactorInteger[n][[All, 1]]}]]] @@ {#, Length@ # + 1} &, {{{1}}}, 105]
%t A334144 (* Second program: *)
%t A334144 g[n_] := Block[{lst = {{n}}}, While[lst[[-1]] != {1}, lst = Join[lst, {Union@ Flatten[# - #/(First@ # & /@ FactorInteger@ #) & /@ lst[[-1]] ]}]]; Max[Length /@ lst]]; Array[g, 105] (* _Robert G. Wilson v_, May 08 2020 *)
%Y A334144 Cf. A064097, A332992, A332999, A333123, A334111, A334184.
%Y A334144 Cf. also A096825.
%K A334144 nonn
%O A334144 1,6
%A A334144 _Michael De Vlieger_, _Peter Kagey_, _Antti Karttunen_, Apr 15 2020