A084688 Nonnegative integers n such that 2^n uses only distinct decimal digits.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 29

Offset

1,3

Comments

There are exactly 18 numbers such that 2^n uses only distinct digits.

a(n) can have at most 10 digits. As 2^34 has 11 digits, a(n) < 34. - David A. Corneth, Aug 03 2015

Subsequence of A052060. - R. J. Mathar, Sep 17 2008

Links

Table of n, a(n) for n=1..18.

Formula

a(n) = log_2(A260814(n)). - Zak Seidov, Aug 02 2015

Example

29 is the last term with 2^29 = 536870912 = A260814(18). - Zak Seidov, Aug 02 2015

Mathematica

Select[Range[0, 34], Max@ DigitCount[2^#] == 1 &] (* Michael De Vlieger, Aug 03 2015 *) (* with corrections by Zak Seidov, Aug 05 2015 *)

Prog

(PARI) lista() = {lim = ceil(log(10^11)/(log(2))); for (n=0, lim, d = digits(2^n); if (#vecsort(d, , 8) == #d, print1(n, ", ")); ); } \\ Michel Marcus, Aug 03 2015

Crossrefs

Cf. A000079, A260814, A052060.

Sequence in context: A252493 A005496 A052060 * A194898 A331271 A267016

Adjacent sequences: A084685 A084686 A084687 * A084689 A084690 A084691

Keyword

fini,nonn,full,base

Author

Zak Seidov, Jul 01 2003

Status

approved