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%I #17 May 09 2021 11:18:50
%S 1,3,23,7,20,29,124,15,147,30,117,41,63,138,296,31,106,165,231,50,84,
%T 139,281,65,294,89,40616,166,212,326,40486,63,377,140,258,201,259,269,
%U 986,90,40589,126,588,183,253,327,40455,113,382,344,514,141,223,40670,41000,222
%N Row sums of irregular triangle A070168.
%C a(n) is the sum of numbers in trajectory of Terras-modified Collatz problem with first number n.
%H Indranil Ghosh, <a href="/A285098/b285098.txt">Table of n, a(n) for n = 1..10000</a>
%e The 5th row of irregular triangle A070168 is [5, 8, 4, 2, 1] whose sum is 20. a(5) = 5 + 8 + 4 + 2 + 1 = 20.
%t a[n_]:=If[n<2, 1, If[OddQ[n], (3n + 1)/2, n/2]]; Table[-1 + Plus @@ FixedPointList[a, n], {n, 100}]
%o (Python)
%o def a(n):
%o if n==1: return 1
%o l=[n]
%o while True:
%o if n%2==0: n//=2
%o else: n = (3*n + 1)//2
%o l.append(n)
%o if n<2: break
%o return sum(l)
%o print([a(n) for n in range(1, 101)])
%Y Cf. A033493, A070168.
%K nonn
%O 1,2
%A _Indranil Ghosh_, Apr 17 2017
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