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A004669
Powers of 3 written in base 27.
1
1, 3, 9, 10, 30, 90, 100, 300, 900, 1000, 3000, 9000, 10000, 30000, 90000, 100000, 300000, 900000, 1000000, 3000000, 9000000, 10000000, 30000000, 90000000, 100000000, 300000000, 900000000, 1000000000
OFFSET
0,2
COMMENTS
Similar to powers of 2 in base 8 (A004647) or 16 (A004655). - M. F. Hasler, Jun 22 2018
FORMULA
a(n) = 3^(n mod 3)*10^floor(n/3). - M. F. Hasler, Jun 22 2018
From Chai Wah Wu, Sep 03 2020: (Start)
a(n) = 10*a(n-3) for n > 2.
G.f.: (-9*x^2 - 3*x - 1)/(10*x^3 - 1). (End)
MATHEMATICA
Table[FromDigits[IntegerDigits[3^n, 27]], {n, 0, 100}] (* G. C. Greubel, Oct 12 2018 *)
PROG
(PARI) apply( a(n)=3^(n%3)*10^(n\3), [0..20]) \\ M. F. Hasler, Jun 22 2018
CROSSREFS
Cf. A000079, A004643, ..., A004655: powers of 2 written in base 10, 4, 5, ..., 16.
Cf. A000244, A004656, A004658, A004659, ..., A004668: powers of 3 in base 10, 2, 4, 5, ..., 26.
Sequence in context: A308084 A136852 A031115 * A173242 A335030 A335029
KEYWORD
nonn,easy,base
STATUS
approved

  NODES
orte 1
see 1
Story 1