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%I #10 Nov 13 2019 00:25:37
%S 3,7,3,6,5,3,3,6,9,12,5,3,3,3,3,6,3,5,4,3,3,3,3,3,6,3,5,4,11,3,3,3,3,
%T 17,3,3,6,3,3,5,11
%N Length of nontrivial cycles under the ghost iteration A329201, as listed in the table A329342.
%C A329201 consists of adding or subtracting the number A040115(n) whose digits are the difference between adjacent digits of n, depending on its parity. Repdigits A010785 are fixed points of this map, but some numbers enter nontrivial cycles. Sequence A329342 lists these cycles, ordered by their smallest member which is always listed first. This sequence gives the row lengths.
%e a(1) = 3 is the length of the first cycle, (8290, 8969, 9102).
%e a(2) = 7 is the length of the next cycle, (17998, 24199, 21819, 20041, 22084, 21800, 20020).
%e a(3) = 3 = a(7) is the length of all members of the family starting with (21901, 23792, 25219) and continued by duplicating the initial digit of each term.
%e a(4) = 6 = a(8) is the length of all members of the family starting with (54503, 55656, 55767, 55978, 56399, 55039), extended as above.
%e a(5) = 5 = a(11) is the length of all members of the family starting with (87290, 88869, 88892, 88909, 89108), extended as above.
%Y Cf. A329342 (table of cycles), A329201, A329197 (analog for A329200), A329198.
%K nonn,more
%O 1,1
%A _M. F. Hasler_, Nov 10 2019
%E a(12) - a(41) from _Scott R. Shannon_, Nov 12 2019