[go: up one dir, main page]

login
A245430
Number of nonnegative integers with property that their base 9/5 expansion (see A024653) has n digits.
0
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
1,1
EXAMPLE
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.
PROG
(Sage)
A=[1]
for i in [1..100]:
A.append(ceil(((9-5)/5)*sum(A)))
[9*x for x in A]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Tom Edgar, Jul 21 2014
STATUS
approved