cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A272826 Cubes whose digits are powers of 2.

Original entry on oeis.org

1, 8, 21811182184
Offset: 1

Views

Author

Waldemar Puszkarz, May 07 2016

Keywords

Comments

Intersection of A028846 and A000578.
1 and 8, as Fibonacci numbers, are also members of A272827.
There are many squares whose digits are powers of 2: 1,4,81,121,144, to name just a few; there are 102 of them up to 10^12. In contrast, there are very few such cubes, only 3 up to 10^18.
Probably this sequence is finite; further terms have at least 31 digits. - Charles R Greathouse IV, May 19 2016

Examples

			21811182184 is a term as its digits are only powers of 2; its cube root is 2794.
		

Crossrefs

Cf. A000578 (cubes), A028846 (numbers whose digits are powers of 2), A272827 (related sequence).

Programs

  • Mathematica
    Select[Range[1000000]^3, SubsetQ[{1,2,4,8}, IntegerDigits@#]&]
  • PARI
    is(n)=ispower(n,3) && #setintersect(Set(digits(n)),[0,3,5,6,7,9])==0 \\ Charles R Greathouse IV, May 08 2016
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