A245416 - OEIS

A245416

Number of nonnegative integers with property that their base 9/2 expansion (see A024650) has n digits.

9, 36, 162, 729, 3276, 14742, 66339, 298530, 1343385, 6045228, 27203526, 122415867, 550871406, 2478921327, 11155145967, 50198156856, 225891705852, 1016512676334, 4574307043503, 20584381695759, 92629717630920, 416833729339140, 1875751782026130

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..23.

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

(Sage)

A=[1]

for i in [1..60]:

A.append(ceil((9-2)/2*sum(A)))

[9*x for x in A]

CROSSREFS

Cf. A024650, A081848.

Sequence in context: A002063 A285674 A075674 * A265837 A264359 A280353

Adjacent sequences: A245413 A245414 A245415 * A245417 A245418 A245419

KEYWORD

nonn,base

AUTHOR

James Van Alstine, Jul 21 2014

STATUS

approved