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

%I #17 Aug 13 2021 11:39:50

%S 1,12,124,337,370,493,616,829,1042,1356,1490,1714,1848,2162,2476,2790,

%T 3014,3238,3462,3776,3910,4044,4448,4852,5166,5390,5524,5748,5972,

%U 6106,6420,6824,7228,7542,7766,7990,8124,8438,8752,8976,9200,9514,9648,9962

%N a(n) = a(n-1) + A073053(a(n-1)).

%C A073053 sequence is operator DENEAT: concatenate number of even digits in n, number of odd digits and total number of digits.

%H Harvey P. Dale, <a href="/A173578/b173578.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = a(n-1)+ A073053(a(n-1)).

%p A173578 := proc(n)

%p option remember;

%p if n = 1 then

%p 1;

%p else

%p procname(n-1)+A073053(procname(n-1)) ;

%p end if;

%p end proc:

%p seq(A173578(n),n=1..20) ; # _R. J. Mathar_, Jul 13 2012

%t 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 easy,nonn,base

%O 1,2

%A _Paolo P. Lava_ & _Giorgio Balzarotti_, Mar 05 2010

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Last modified April 25 12:53 EDT 2024. Contains 371969 sequences. (Running on oeis4.)