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A173578 a(n) = a(n-1) + A073053(a(n-1)).

%I A173578 #17 Aug 13 2021 11:39:50
%S A173578 1,12,124,337,370,493,616,829,1042,1356,1490,1714,1848,2162,2476,2790,
%T A173578 3014,3238,3462,3776,3910,4044,4448,4852,5166,5390,5524,5748,5972,
%U A173578 6106,6420,6824,7228,7542,7766,7990,8124,8438,8752,8976,9200,9514,9648,9962
%N A173578 a(n) = a(n-1) + A073053(a(n-1)).
%C A173578 A073053 sequence is operator DENEAT: concatenate number of even digits in n, number of odd digits and total number of digits.
%H A173578 Harvey P. Dale, <a href="/A173578/b173578.txt">Table of n, a(n) for n = 1..1000</a>
%F A173578 a(n) = a(n-1)+ A073053(a(n-1)).
%p A173578 A173578 := proc(n)
%p A173578     option remember;
%p A173578     if n = 1 then
%p A173578         1;
%p A173578     else
%p A173578         procname(n-1)+A073053(procname(n-1)) ;
%p A173578     end if;
%p A173578 end proc:
%p A173578 seq(A173578(n),n=1..20) ; # _R. J. Mathar_, Jul 13 2012
%t A173578 deneat[n_]:=Module[{idn=IntegerDigits[n]},FromDigits[ Flatten[ IntegerDigits/@ {Count[ idn,_?EvenQ],Count[ idn,_?OddQ],Length[ idn]}]]]; NestList[ #+deneat[ #]&,1,50] (* _Harvey P. Dale_, Aug 13 2021 *)
%K A173578 easy,nonn,base
%O A173578 1,2
%A A173578 _Paolo P. Lava_ & _Giorgio Balzarotti_, Mar 05 2010