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%I #11 Oct 13 2024 00:17:48
%S 1,10,11,12,13,14,15,16,17,18,19,20,24,26,27,28,30,33,35,36,37,38,39,
%T 40,42,43,44,45,46,47,48,49,50
%N Numbers m such that the resulting number h after iterations of {((((D_1^D_2)^D_3)^D_4)^...)^D_k, where D_k is the k-th digit D of the number r and k is the digit number of the number r in the decimal expansion of r (A055642)} needed to reach a one-digit number starting at r = n is equal to 1 (h = 1).
%e For number a(14) = 26 we have iteration: {2^6 = 64}, {6^4 = 1296}, {((1^2)^9)^6 = 1}.
%Y Cf. A175398, A175399, A175400, A175401, A175402, A175403.
%K nonn,base,more
%O 1,2
%A _Jaroslav Krizek_, May 01 2010