A245429 Number of nonnegative integers with property that their base 9/7 expansion (see A024655) has n digits.

9, 9, 9, 9, 18, 18, 27, 36, 45, 54, 72, 90, 117, 153, 198, 252, 324, 414, 531, 684, 882, 1134, 1458, 1872, 2412, 3096, 3978, 5121, 6579, 8460, 10881, 13986, 17982, 23121, 29727, 38223, 49140, 63180, 81234, 104445, 134280, 172647, 221976, 285399, 366939, 471780

Offset: 1

Author

Hailey R. Olafson, Jul 21 2014

Keywords

• nonn
• base

Examples

			a(2) = 9 because 70, 71, 72, 73, 74, 75, 76, 77 and 78 are the base 9/7 expansions for the integers 9, 10, 11, 12, 13, 14, 15, 16 and 17 respectively and these are the only integers with 2 digits.
		

Crossrefs

Cf. A024655, A081848, A245356.

Programs

Sage

A=[1]
for i in [1..60]:
    A.append(ceil(((9-7)/7)*sum(A)))
[9*x for x in A]