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%I #11 Nov 04 2024 09:30:45
%S 2,1,1,1,1,122,121,121,120,120,122,121,121,120,120,120,120,119,118,
%T 119,120,120,119,118,119,118,118,117,117,117,118,118,117,117,117,117,
%U 116,116,116,116,117,116,116,116,116,115,115,4,115,4,115,115,4,115,4,114,114,114,114,3,114,114,114,114,3,3,113,3,113,2,3,113,3,113
%N Number of terms in the "comma sum" sequence (cf. A230288) starting with n, or 0 if it is infinite.
%C A "comma sum" sequence is such that a(n+1)-a(n) = rightmost digit of a(n) + leftmost digit of a(n+1), taking usually the smallest possible solution.
%C The value a(0)=2 corresponds to the sequence (0,1), not to sequence A230288 starting by definition with 0,5,....
%C a(n)>0 for all n<396. See A230450 for the sequence starting with 396.
%o (PARI) for(n=0,196,print1(#A230288_list([n],150),",")) \\ The second argument (nMax) is useful only for n>= 396. If this value (here 150) is printed, this most probably means that the sequence is infinite, a(n)=0.
%o (Python) # uses A230288gen() in A230288
%o def a(n): return len(list(A230288gen(start=[n])))
%o print([a(n) for n in range(100)]) # _Michael S. Branicky_, Nov 03 2024
%Y Cf. A230288, A230450, A230452.
%K nonn,base
%O 0,1
%A _M. F. Hasler_, Oct 19 2013