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Number of nonnegative integers with property that their base 9/8 expansion (see A024656) has n digits.
0

%I #10 Jul 22 2014 22:18:02

%S 9,9,9,9,9,9,9,9,9,18,18,18,18,27,27,27,36,36,45,45,54,63,72,81,90,99,

%T 108,126,144,162,180,198,225,252,288,324,360,405,459,513,576,648,729,

%U 819,927,1044,1170,1314,1485,1665,1872,2106,2376,2673,3006,3384,3807

%N Number of nonnegative integers with property that their base 9/8 expansion (see A024656) has n digits.

%F a(n) = 9*A120194(n).

%e a(2) = 9 since 80, 81, 82, 83, 84, 85, 86, 87, 88 are the base 9/8 representations of 9-17 respectively and these are the only integers with 2 digits.

%o (Sage)

%o A=[1]

%o for i in [1..100]:

%o A.append(ceil(((9-8)/8)*sum(A)))

%o [9*x for x in A]

%Y Cf. A245356, A120194, A024656, A081848.

%K nonn,base

%O 1,1

%A _Tom Edgar_, Jul 21 2014