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A129888 Start with 10; write down the sum of its digits; add last two terms; repeat.

%I A129888 #16 Oct 01 2021 10:28:15
%S A129888 10,1,11,2,13,4,17,8,25,7,32,5,37,10,47,11,58,13,71,8,79,16,95,14,109,
%T A129888 10,119,11,130,4,134,8,142,7,149,14,163,10,173,11,184,13,197,17,214,7,
%U A129888 221,5,226,10,236,11,247,13,260,8,268,16,284,14,298,19,317,11,328,13
%N A129888 Start with 10; write down the sum of its digits; add last two terms; repeat.
%H A129888 Michael S. Branicky, <a href="/A129888/b129888.txt">Table of n, a(n) for n = 1..10000</a>
%F A129888 a(2n+1)=A007618(n+2). For 1<=n<=10: a(2n)=A065075(n+1). - _R. J. Mathar_, Jun 14 2007
%t A129888 nxt[n_]:=Module[{t=Total[n]},{t,Total[IntegerDigits[t]]}]; Flatten[ NestList[ nxt,{10,1},35]] (* _Harvey P. Dale_, Mar 29 2011 *)
%o A129888 (Python)
%o A129888 def next2(n): sd = sum(map(int, str(n))); return [sd, n+sd]
%o A129888 def aupton(terms):
%o A129888     alst = [10]
%o A129888     while len(alst) < terms: alst.extend(next2(alst[-1]))
%o A129888     return alst[:terms]
%o A129888 print(aupton(66)) # _Michael S. Branicky_, Oct 01 2021
%Y A129888 Cf. A007618, A065075.
%K A129888 nonn,base
%O A129888 1,1
%A A129888 _N. J. A. Sloane_, May 26 2007
%E A129888 More terms from _R. J. Mathar_, Jun 14 2007