A245429
Number of nonnegative integers with property that their base 9/7 expansion (see A024655) has n digits.
Original entry on oeis.org
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
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.
A245430
Number of nonnegative integers with property that their base 9/5 expansion (see A024653) has n digits.
Original entry on oeis.org
9, 9, 18, 36, 63, 108, 198, 360, 648, 1161, 2088, 3762, 6768, 12186, 21933, 39483, 71064, 127917, 230256, 414459, 746028, 1342845, 2417121, 4350816, 7831476, 14096655, 25373979, 45673164, 82211688, 147981042, 266365872, 479458575, 863025435, 1553445783, 2796202404
Offset: 1
The numbers 9-17 are represented by 50, 51, 52, 53, 54, 55, 56, 57, 58 respectively in base 9/5. Since these are the only two digit integers we have a(2) = 9.
A245431
Number of nonnegative integers with property that their base 10/7 expansion has n digits.
Original entry on oeis.org
10, 10, 10, 20, 30, 40, 60, 80, 120, 170, 240, 340, 490, 700, 1000, 1430, 2040, 2910, 4160, 5940, 8490, 12130, 17330, 24750, 35360, 50520, 72170, 103100, 147280, 210400, 300570, 429390, 613410, 876300, 1251860, 1788370, 2554820, 3649740, 5213910, 7448450
Offset: 1
a(2) = 10 because 70, 71, 72, 73, 74, 75, 76, 77, 78 and 79 are the base 10/7 expansions for the integers 10, 11, 12, 13, 14, 15, 16, 17, 18 and 19 respectively and these are the only integers with 2 digits.
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