%I #20 Aug 08 2023 09:13:13
%S 6,6,6,6,6,6,12,12,12,18,18,24,30,36,42,48,60,72,84,102,126,150,180,
%T 216,258,312,372,444,534,642,768,924,1110,1332,1596,1914,2298,2760,
%U 3312,3972,4770,5724,6864,8238,9888,11862,14238,17082,20502,24600,29520,35424
%N Number of nonnegative integers with property that their base 6/5 expansion (see A024638) has n digits.
%H G. C. Greubel, <a href="/A245399/b245399.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Ba#base_fractional">Index entries for sequences related to fractional bases</a>
%F a(n) = 6*A120170(n).
%e a(3) = 6 because 540, 541, 542, 543, 544 and 545 are the base 6/5 expansions for the integers 12, 13, 14, 15, 16 and 17 respectively and these are the only integers with 3 digits.
%t A120170[n_]:= A120170[n] = If[n==1, 1, Ceiling[Sum[A120170[j], {j, n-1}]/5]]; Table[6*A120170[n], {n, 60}] (* _G. C. Greubel_, Aug 19 2019 *)
%o (Sage)
%o A=[1]
%o for i in [1..60]:
%o A.append(ceil(((6-5)/5)*sum(A)))
%o [6*x for x in A]
%Y Cf. A024638, A081848, A120170, A245356.
%K nonn,base
%O 1,1
%A _Hailey R. Olafson_, Jul 21 2014