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A245403
Number of nonnegative integers with property that their base 10/9 expansion (see A024664) has n digits.
0
10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 20, 20, 20, 20, 20, 30, 30, 30, 40, 40, 50, 50, 60, 60, 70, 80, 90, 100, 110, 120, 130, 150, 160, 180, 200, 220, 250, 280, 310, 340, 380, 420, 470, 520, 580, 640, 710, 790, 880, 980, 1090, 1210, 1340, 1490, 1660
OFFSET
1,1
FORMULA
a(n) = 10*A120202(n).
EXAMPLE
The numbers 10-19 are represented by 90, 91, 92, 93, 94, 95, 96, 97, 98, 99 respectively in base 10/9. These are the only integers with two digits, and so a(2)=10.
PROG
(Sage)
A=[1]
for i in [1..60]:
A.append(ceil((10-9)/9*sum(A)))
[10*x for x in A]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
James Van Alstine, Jul 21 2014
STATUS
approved