A217009 Multiples of 7 in base 8.

7, 16, 25, 34, 43, 52, 61, 70, 77, 106, 115, 124, 133, 142, 151, 160, 167, 176, 205, 214, 223, 232, 241, 250, 257, 266, 275, 304, 313, 322, 331, 340, 347, 356, 365, 374, 403, 412, 421, 430, 437, 446, 455, 464, 473, 502, 511, 520, 527, 536, 545, 554, 563

Offset

1,1

Comments

Digit sum is always divisible by 7.

Reinterpreting this sequence in base 10, these are numbers of the form 9n + 7 but with all numbers containing 8s and/or 9s removed. - Alonso del Arte, Sep 23 2012

Links

Table of n, a(n) for n=1..53.

Formula

a(n) = A007094(A008589(n)). -

Example

a(10) = 106 because 7 * 10 = 70, or 1 * 8^2 + 0 * 8^1 + 6 * 8^0 = 64 + 6 = 106_8.

Mathematica

Table[BaseForm[7*n, 8], {n, 100}] (* Alonso del Arte, Sep 23 2012 *)
Select[9*Range[0, 99] + 7, DigitCount[#, 10, 8] == 0 && DigitCount[#, 10, 9] == 0 &] (* Alonso del Arte, Sep 23 2012 *)
Table[FromDigits[IntegerDigits[7*n, 8]], {n, 100}] (* T. D. Noe, Sep 24 2012 *)

Prog

(JavaScript)
k = 7;
for (i = 1; i <= 200; i++) {
x = i * k;
document.write(x.toString(k + 1) + ", ");
}

Crossrefs

Cf. A216994, A216995, A216996, A216997, A216998.

Cf. A008589.

Sequence in context: A367084 A273159 A043481 * A017245 A052221 A119461

Adjacent sequences: A217006 A217007 A217008 * A217010 A217011 A217012

Keyword

nonn,base,easy

Author

Jon Perry, Sep 23 2012

Status

approved