A261232 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).

1, 2, 4, 9, 21, 50, 124, 320, 850, 2295, 6251, 17113, 47014, 129606, 358839, 998806, 2796094, 7869801, 22251148, 63141640, 179701240, 512744600, 1466635090, 4205423896, 12087339724, 34816804311, 100469592522, 290336059741, 839932833291, 2432050970421, 7047731703138, 20440131344751, 59334695322384, 172409162871824, 501489513690424

Offset: 0

Author

Antti Karttunen, Aug 13 2015

Keywords

• nonn

Crossrefs

One more than A261233.

Cf. A000244, A261231.

Cf. also A213710.

Formula

a(0) = 1; for n >= 1, a(n) = A261234(n-1) + a(n-1).

a(n) = A261231(3^n).

a(n) = 1 + A261233(n).

Extensions

Terms from a(24) onward added from the output of Hiroaki Yamanouchi's program by Antti Karttunen, Aug 16 2015