%I #2 Oct 27 2023 22:00:47

%S 2,11,20,101,110,134,136,163,172,197,200,217,233,242,244,262,278,287,

%T 296,298,307,313,314,316,343,359,386,397,406,413,422,424,431,433,442,

%U 458,467,469,476,478,487,514,523,541,577,583,586,593,604,613,614,622

%N The iterative cycle: n -> sum of digits of n^2 has only four distinct elements.

%e a(2) = 4 since 2 -> 4 -> 1+6 = 7 -> 4+9 = 13 -> 1+6+9 = 16 -> 2+5+6 = 13, thus {4,7,13,16} are the distinct elements of the iterative cycle of 2.

%Y Cf. A007953, A004159, A061903 - A061910.

%K nonn,base

%O 1,1

%A _Asher Auel_, May 17 2001