A057104 The non-octal numbers: numbers containing an 8 or 9 (they cannot be mistaken for octal numbers).

8, 9, 18, 19, 28, 29, 38, 39, 48, 49, 58, 59, 68, 69, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 108, 109, 118, 119, 128, 129, 138, 139, 148, 149, 158, 159, 168, 169, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188

Offset: 1

Author

Thomas Schulze (jazariel(AT)tiscalenet.it), Sep 12 2000

Keywords

• easy
• nonn
• base

Examples

			'42' might be read as an octal number, but '48' could not be and so belongs to the sequence.
		

Crossrefs

Cf. A007094.

Programs

Mathematica

Select[Range[200],Max[IntegerDigits[#]]>7&] (* Harvey P. Dale, May 26 2018 *)

PARI

isok(n) = vecmax(digits(n)) > 7; \\ Michel Marcus, Feb 18 2016

Python

def ok(n): return {'8', '9'} & set(str(n)) != set()
print(list(filter(ok, range(189)))) # Michael S. Branicky, Aug 09 2021