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%I #36 Jun 23 2017 19:12:42
%S 25,27,32,49,54,64,81,96,98,121,125,128,135,147,162,169,189,192,216,
%T 224,242,243,245,250,256,289,297,320,338,343,351,352,361,363,375,384,
%U 392,405,416,432,448,486,500,507,512,513,529,539,567,576,578,605,621,625,637,640,648,675,686,704,722,729,736,750,768,775,783,784
%N Numbers n for which A230625(n) < n, where A230625 is the concatenation of the prime factorization written in binary, converted back to decimal.
%C Relevant for the study of closed orbits. (This is to A230625 the analog of A195330 for A080670.) Up to a certain limit, the trajectory of all numbers, under iteration of A230625, end either in a prime (fixed point) or in one of the orbits {1007, 1269} or {1503,3751}.
%C See A288985 for the analog when A287874 is used instead of A230625, i.e., without converting back the concatenation of the binary strings to decimal, or rather, reading it as a decimal number.
%t Select[Range@ 800, Function[n, FromDigits[#, 2] < n &@ Flatten@ Map[IntegerDigits[#, 2] &, FactorInteger[n] /. {p_, 1} :> {p}]]] (* _Michael De Vlieger_, Jun 23 2017 *)
%o (PARI) forcomposite(n=1,1e6,A230625(n)<n&&print1(n","))
%Y Cf. A230625, A195330, A080670, A287874.
%K nonn,base
%O 1,1
%A _M. F. Hasler_, Jun 21 2017
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