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A245416
Number of nonnegative integers with property that their base 9/2 expansion (see A024650) has n digits.
0
9, 36, 162, 729, 3276, 14742, 66339, 298530, 1343385, 6045228, 27203526, 122415867, 550871406, 2478921327, 11155145967, 50198156856, 225891705852, 1016512676334, 4574307043503, 20584381695759, 92629717630920, 416833729339140, 1875751782026130
OFFSET
1,1
EXAMPLE
The numbers 9-44 are represented by 20, 21, 22, 23, 24, 25, 26, 27, 28, 40, 41, 42, 43, 44, 45, 46, 47, 48, 60, 61, 62, 63, 64, 65, 66, 67, 68, 80, 81, 82, 83, 84, 85, 86, 87, 88 respectively in base 9/2. These are the only integers with two digits, and so a(2)=36.
PROG
(SageMath)
A=[1]
for i in [1..60]:
A.append(ceil((9-2)/2*sum(A)))
[9*x for x in A]
CROSSREFS
Sequence in context: A002063 A285674 A075674 * A265837 A383072 A383354
KEYWORD
nonn,base
AUTHOR
James Van Alstine, Jul 21 2014
STATUS
approved