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A246700 Table read by rows: trajectories under iteration of Carmichael's lambda function (cf. A002322).

%I A246700 #15 Aug 18 2024 20:20:03
%S A246700 1,2,1,3,2,1,4,2,1,5,4,2,1,6,2,1,7,6,2,1,8,2,1,9,6,2,1,10,4,2,1,11,10,
%T A246700 4,2,1,12,2,1,13,12,2,1,14,6,2,1,15,4,2,1,16,4,2,1,17,16,4,2,1,18,6,2,
%U A246700 1,19,18,6,2,1,20,4,2,1,21,6,2,1,22,10,4,2,1
%N A246700 Table read by rows: trajectories under iteration of Carmichael's lambda function (cf. A002322).
%C A246700 Length of row n = A185816(n) + 1.
%H A246700 Reinhard Zumkeller, <a href="/A246700/b246700.txt">Rows n = 1..1001 of triangle, flattened</a>
%F A246700 T(n,1) = n and T(n,k+1) = A002322(T(n,k)), k = 1..A185816(n).
%e A246700 .   |  1 | 1             | 13 | 13-12-2-1        | 25 | 25-20-4-2-1
%e A246700 .   |  2 | 2-1           | 14 | 14-6-2-1         | 26 | 26-12-2-1
%e A246700 .   |  3 | 3-2-1         | 15 | 15-4-2-1         | 27 | 27-18-6-2-1
%e A246700 .   |  4 | 4-2-1         | 16 | 16-4-2-1         | 28 | 28-6-2-1
%e A246700 .   |  5 | 5-4-2-1       | 17 | 17-16-4-2-1      | 29 | 29-28-6-2-1
%e A246700 .   |  6 | 6-2-1         | 18 | 18-6-2-1         | 30 | 30-4-2-1
%e A246700 .   |  7 | 7-6-2-1       | 19 | 19-18-6-2-1      | 31 | 31-30-4-2-1
%e A246700 .   |  8 | 8-2-1         | 20 | 20-4-2-1         | 32 | 32-8-2-1
%e A246700 .   |  9 | 9-6-2-1       | 21 | 21-6-2-1         | 33 | 33-10-4-2-1
%e A246700 .   | 10 | 10-4-2-1      | 22 | 22-10-4-2-1      | 34 | 34-16-4-2-1
%e A246700 .   | 11 | 11-10-4-2-1   | 23 | 23-22-10-4-2-1   | 35 | 35-12-2-1
%e A246700 .   | 12 | 12-2-1        | 24 | 24-2-1           | 36 | 36-6-2-1  .
%t A246700 Array[Most[FixedPointList[CarmichaelLambda, #]] &, 25] (* _Paolo Xausa_, Aug 17 2024 *)
%o A246700 (Haskell)
%o A246700 import Data.List (genericIndex)
%o A246700 a246700 n k = genericIndex a246700_tabf (n - 1) !! (k-1)
%o A246700 a246700_row n = genericIndex a246700_tabf (n - 1)
%o A246700 a246700_tabf = [1] : f 2  where
%o A246700    f x = (x : a246700_row (a002322 x)) : f (x + 1)
%Y A246700 Cf. A002322, A185816, A375478.
%K A246700 nonn,tabf
%O A246700 1,2
%A A246700 _Reinhard Zumkeller_, Sep 02 2014