A033033 Numbers all of whose base 7 digits are odd.

1, 3, 5, 8, 10, 12, 22, 24, 26, 36, 38, 40, 57, 59, 61, 71, 73, 75, 85, 87, 89, 155, 157, 159, 169, 171, 173, 183, 185, 187, 253, 255, 257, 267, 269, 271, 281, 283, 285, 400, 402, 404, 414, 416, 418, 428, 430, 432, 498, 500, 502, 512

Offset

1,2

Links

David A. Corneth, Table of n, a(n) for n = 1..10000

Example

38 in base 7 is 53_7. All the digits of 38 in base 7; 5 and 3; are odd. So 38 is in the sequence. - David A. Corneth, Aug 24 2019

Mathematica

Select[Range[600], AllTrue[IntegerDigits[#, 7], OddQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Sep 28 2014 *)

Prog

(PARI) is(n) = {my(d = Set(digits(n, 7))); for(i = 1, #d, if(d[i]%2 == 0, return(0))); 1} \\ David A. Corneth, Aug 24 2019
(Magma) [m:m in [1..600]| Intseq(m, 7) subset {1, 3, 5}]; // Marius A. Burtea, Aug 24 2019

Crossrefs

Cf. A007093, A014261.

Sequence in context: A287236 A305378 A362935 * A211704 A275813 A356037

Adjacent sequences: A033030 A033031 A033032 * A033034 A033035 A033036

Keyword

nonn,easy,base

Author

Clark Kimberling

Status

approved