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%I #47 Oct 29 2021 06:06:34
%S 2,1,4,1,6,3,8,1,10,5,11,5,12,3,14,7,16,1,18,9,22,5
%N Two-column array A(n,s) of pairs (n,s) read by row where s is the smallest seed number such that the Reverse and Add! trajectory of s contains n (excluding cases where n=s).
%H Felix Fröhlich, <a href="/A243824/a243824_1.txt">C++ program for this sequence</a>
%e A(10,1)=16 is in the array because 16 is the 9th number appearing in the Reverse and Add! trajectory of a smaller number.
%e A(10,2)=1 is in the array because 1 + 1 = 2, 2 + 2 = 4, 4 + 4 = 8, 8 + 8 = 16, so 1 is the smallest seed number whose Reverse and Add! trajectory contains 16.
%e Array begins:
%e 2 1
%e 4 1
%e 6 3
%e 8 1
%e 10 5
%e 11 5
%e 12 3
%e 14 7
%e 16 1
%e 18 9
%e 22 5
%Y Cf. A006960, A023109, A033665, A063048, A070788, A077594.
%K nonn,base,tabf,more
%O 2,1
%A _Felix Fröhlich_, Jun 11 2014