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%I #16 Mar 30 2017 21:53:25
%S 1,2,4,9,21,50,124,320,850,2295,6251,17113,47014,129606,358839,998806,
%T 2796094,7869801,22251148,63141640,179701240,512744600,1466635090,
%U 4205423896,12087339724,34816804311,100469592522,290336059741,839932833291,2432050970421,7047731703138,20440131344751,59334695322384,172409162871824,501489513690424
%N a(n) = number of steps to reach 0 when starting from k = 3^n and repeatedly applying the map that replaces k with k - (sum of digits in base-3 representation of k).
%F a(0) = 1; for n >= 1, a(n) = A261234(n-1) + a(n-1).
%F a(n) = A261231(3^n).
%F a(n) = 1 + A261233(n).
%o (Scheme, two variants)
%o (definec (A261232 n) (if (zero? n) 1 (+ (A261234 (- n 1)) (A261232 (- n 1)))))
%o (define (A261232 n) (A261231 (A000244 n)))
%Y One more than A261233.
%Y Cf. A000244, A261231.
%Y Cf. also A213710.
%K nonn
%O 0,2
%A _Antti Karttunen_, Aug 13 2015
%E Terms from a(24) onward added from the output of _Hiroaki Yamanouchi_'s program by _Antti Karttunen_, Aug 16 2015
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