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Number of 9's when k is written in base b for all b and k satisfying 2<=b<=n+1, 1<=k<=n.
10

%I #7 Nov 15 2012 04:28:00

%S 0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,2,3,4,5,6,7,8,9,10,11,13,14,16,

%T 17,19,20,22,23,25,26,29,30,32,34,36,37,40,41,43,45,48,49,52,53,56,58,

%U 60,61,65,66,69,71,74,75,78,80,83,85,87,88,94

%N Number of 9's when k is written in base b for all b and k satisfying 2<=b<=n+1, 1<=k<=n.

%t f[n_] := Count[ Flatten@ Table[ IntegerDigits[k, b], {k, n}, {b, 2, n + 1}], 9] - (n - 9); f[1] = f[2] = f[3] = f[4] = f[5] = f[6] = f[7] = f[8] = 0; Array[f, 69] (* _Robert G. Wilson v_, Nov 14 2012 *)

%Y Cf. A033094, A033096, A033098, A033100, A033102, A033104, A033106, A033108, A033110, A033111.

%K nonn,base

%O 1,19

%A _Clark Kimberling_