A004656 Powers of 3 written in base 2.

1, 11, 1001, 11011, 1010001, 11110011, 1011011001, 100010001011, 1100110100001, 100110011100011, 1110011010101001, 101011001111111011, 10000001101111110001, 110000101001111010011, 10010001111101101111001

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• base
• easy

References

• S. Wolfram, A New Kind of Science, Wolfram Media, 2002, pp. 120 and 903.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..640

Crossrefs

Cf. A000079, A004643, ..., A004655: powers of 2 written in base 10, 4, 5, ..., 16

Cf. A000244, A004658, A004659, ... : powers of 3 written in base 10, 4, 5, ...

Programs

Magma

[Seqint(Intseq(3^n, 2)): n in [0..30]]; // G. C. Greubel, Sep 10 2018

Mathematica

Table[ FromDigits[ IntegerDigits[3^n, 2]], {n, 0, 14}]

PARI

a(n)=fromdigits(binary(3^n)) \\ M. F. Hasler, Jun 23 2018