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A033860 Sort-then-add sequence: a(n+1) = a(n) + sort(a(n)).

%I A033860 #15 Jan 15 2024 15:10:50
%S A033860 1,2,4,8,16,32,55,110,121,233,466,932,1171,2288,4576,9143,10492,11741,
%T A033860 22888,45776,91453,104912,116161,227327,449704,494183,628672,855350,
%U A033860 890908,899807,978706,1046495,1191064,1302533,1425868,2671556,3927223,6150602,6163168
%N A033860 Sort-then-add sequence: a(n+1) = a(n) + sort(a(n)).
%H A033860 Reinhard Zumkeller, <a href="/A033860/b033860.txt">Table of n, a(n) for n = 1..10000</a>
%F A033860 a(n+1) = A070196(a(n)). - _Reinhard Zumkeller_, Apr 03 2015
%e A033860 After 9143 the next term is 9143 + 1349 = 10492.
%p A033860 a:= proc(n) option remember; `if`(n=1, 1, (t->
%p A033860       t+parse(cat(sort(convert(t, base, 10))[])))(a(n-1)))
%p A033860     end:
%p A033860 seq(a(n), n=1..40);  # _Alois P. Heinz_, Jan 15 2024
%t A033860 NestList[#+FromDigits[Sort[IntegerDigits[#]]]&,1,40] (* _Harvey P. Dale_, Jul 24 2016 *)
%o A033860 (Haskell)
%o A033860 a033860 n = a033860_list !! (n-1)
%o A033860 a033860_list = iterate a070196 1
%o A033860 -- _Reinhard Zumkeller_, Apr 03 2015
%o A033860 (Python)
%o A033860 from itertools import islice
%o A033860 def agen(an=1): # generator of terms
%o A033860     while True: yield an; an = an + int("".join(sorted(str(an))))
%o A033860 print(list(islice(agen(), 100))) # _Michael S. Branicky_, Jan 15 2024
%Y A033860 Cf. A070196, A004185.
%K A033860 nonn,base
%O A033860 1,2
%A A033860 _David W. Wilson_