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A098949 Numbers where 9 is the only odd decimal digit. 2
9, 29, 49, 69, 89, 90, 92, 94, 96, 98, 99, 209, 229, 249, 269, 289, 290, 292, 294, 296, 298, 299, 409, 429, 449, 469, 489, 490, 492, 494, 496, 498, 499, 609, 629, 649, 669, 689, 690, 692, 694, 696, 698, 699, 809, 829, 849, 869, 889, 890, 892, 894, 896, 898 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This is a regular language in base 10. - Charles R Greathouse IV, Oct 05 2011

The number of terms of this sequence that are smaller than 10^n is n*5^(n-1). - Stefan Steinerberger, Jun 06 2006

Any number of 9s is permitted. - Harvey P. Dale, May 07 2019

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..2000

Index entries for 10-automatic sequences

MATHEMATICA

Select[Range[1000], DigitCount[ # ][[1]] == 0 && DigitCount[ # ][[3]] == 0 && DigitCount[ # ][[5]] == 0 && DigitCount[ # ][[7]] == 0 && DigitCount[ # ][[9]] >0 &] (* Stefan Steinerberger, Jun 06 2006; corrected by Harvey P. Dale, May 07 2019 *)

Select[Range[1000], Union[Select[IntegerDigits[#], OddQ]]=={9}&] (* Harvey P. Dale, May 07 2019 *)

PROG

(Perl) for (0..1000) {

    print "$_, " if (/^[024689]*9[024689]*$/)

} # Charles R Greathouse IV, Oct 05 2011

(Python)

def ok(n): return set(str(n)) & set("13579") == set("9")

print(list(filter(ok, range(899)))) # Michael S. Branicky, Sep 29 2021

CROSSREFS

Sequence in context: A002642 A032700 A322946 * A031296 A146869 A129397

Adjacent sequences:  A098946 A098947 A098948 * A098950 A098951 A098952

KEYWORD

base,easy,nonn

AUTHOR

Eric Angelini, Oct 21 2004

EXTENSIONS

More terms from Stefan Steinerberger, Jun 06 2006

STATUS

approved

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Last modified October 27 13:43 EDT 2021. Contains 348276 sequences. (Running on oeis4.)