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%I A073053
%S A073053 11,101,11,101,11,101,11,101,11,112,22,112,22,112,22,112,22,112,22,
%T A073053 202,112,202,112,202,112,202,112,202,112,112,22,112,22,112,22,112,
%U A073053 22,112,22,202,112,202,112,202,112,202,112,202,112,112,22,112,22
%N A073053 Apply DENEAT operator to n.
%C A073053 DENEAT(n): concatenate number of even digits in n, number of odd digits 
               and total number of digits. E.g. 25 -> 1.1.2 = 112 (Digits: Even, 
               Not Even, And Total). Leading zeros are then omitted.
%C A073053 Repeated application of the DENEAT operator reduces all numbers to 123. 
               This is easy to prove. Compare A100961. - N. J. A. Sloane (njas(AT)research.att.com) 
               Jun 18 2005
%D A073053 M. Ecker, Caution: Black Holes at Work, New Scientist (Dec. 1992)
%D A073053 M. J. Halm, Blackholing, Mpossibilities 69, (Jan 01 1999), p. 2.
%e A073053 a(1) = 0.1.1 -> 11.
%e A073053 a(10000000000) = 10111 because 10000000000 has 10 even digits, 1 odd 
               digit and 11 total digits
%t A073053 f[n_] := Block[{id = IntegerDigits[n]}, FromDigits[ Join[ IntegerDigits[ 
               Length[ Select[id, EvenQ[ # ] &]]], IntegerDigits[ Length[ Select[id, 
               OddQ[ # ] &]]], IntegerDigits[ Length[ id]] ]]]; Table[ f[n], {n, 
               0, 55}] (from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 09 2005)
%t A073053 s={};Do[id=IntegerDigits[n];ev=Select[id, EvenQ];ne=Select[id, OddQ];
               fd=FromDigits[{Length[ev], Length[ne], Length[id]}]; s=Append[s, 
               fd], {n, 81}];SameQ[newA073053-s] (Zak Seidov)
%Y A073053 Cf. A008577, A072420, A073054, A100961.
%Y A073053 Sequence in context: A103720 A127806 A036929 this_sequence A133835 A043494 
               A038444
%Y A073053 Adjacent sequences: A073050 A073051 A073052 this_sequence A073054 A073055 
               A073056
%K A073053 easy,nonn,base
%O A073053 1,1
%A A073053 Michael Joseph Halm (hierogamous(AT)lycos.com), Aug 16 2002
%E A073053 Edited and corrected by Jason Earls (zevi_35711(AT)yahoo.com) and Robert 
               G. Wilson v (rgwv(AT)rgwv.com), Jun 03 2005

    
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Last modified December 6 13:45 EST 2009. Contains 170429 sequences.


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