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%I #13 Jan 12 2019 02:27:31
%S 1,16,9,16,9,9,0,16,9,1,0,9,16,9,9,16,48,9,16,16,9,0,9,9,9,9,9,9,0,9,
%T 16,9,0,0,16,9,16,0,9,16,9,9,0,0,9,16,0,48,0,9,9,9,16,9,0,0,9,9,0,9,
%U 16,9,9,16,0,0,16,9,9,0
%N Smallest value of the loop in which n ends, when iterating the map (A257588) which sends a number to absolute value of first digit squared minus second digit squared plus third digit squared etc.
%C Six loops are possible. There are three loops of one.
%C 21.0% of the numbers end up as zero.
%C Some numbers end up as a happy number (=1); density is 4.2%.
%C Some numbers end up as 48; density is 4.8%.
%C More numbers end up in a loop of two (16 and 35); density is 25.4%.
%C Most numbers end up in a loop of five (9, 81, 63, 27, 45, 9); density is 44.6%.
%H Pieter Post, <a href="/A257796/b257796.txt">Table of n, a(n) for n = 1..999</a>
%e a(17)=48 because abs(1^2 - 7^2) = 48 => abs(4^2 - 8^2) = 48.
%e a(34)=0 because abs(3^2 - 4^2) = 7 => 7^2 = 49 => abs(4^2 - 9^2) = 65 => abs(6^2 - 5^2) = 11 => abs(1^2 - 1^2) = 0.
%Y Cf. A007770, A090425, A257588.
%K nonn,base
%O 1,2
%A _Pieter Post_, May 09 2015
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