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A098948 Numbers where 7 is the only odd decimal digit. 1
7, 27, 47, 67, 70, 72, 74, 76, 77, 78, 87, 207, 227, 247, 267, 270, 272, 274, 276, 277, 278, 287, 407, 427, 447, 467, 470, 472, 474, 476, 477, 478, 487, 607, 627, 647, 667, 670, 672, 674, 676, 677, 678, 687, 700, 702, 704, 706, 707, 708, 720, 722, 724, 726 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This is a 10-automatic language. - Charles R Greathouse IV, Oct 03 2011

LINKS

Table of n, a(n) for n=1..54.

Index entries for 10-automatic sequences

MAPLE

q:= n-> is(select(c-> c::odd, {convert(n, base, 10)[]})={7}):

select(q, [$1..887])[];  # Alois P. Heinz, Jul 27 2021

MATHEMATICA

Select[Range[1000], Union[Select[IntegerDigits[#], OddQ]]=={7}&] (* Harvey P. Dale, May 24 2012 *)

PROG

(Perl) for (0..1000) {

    print "$_, " if (/^[024678]*7[024678]*$/)

} # Charles R Greathouse IV, Oct 05 2011

(Python)

def ok(n): return set("13579") & set(str(n)) == {'7'}

print(list(filter(ok, range(727)))) # Michael S. Branicky, Jul 27 2021

CROSSREFS

Sequence in context: A323113 A205861 A215446 * A015873 A344721 A309335

Adjacent sequences:  A098945 A098946 A098947 * A098949 A098950 A098951

KEYWORD

base,easy,nonn

AUTHOR

Eric Angelini, Oct 21 2004

STATUS

approved

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Last modified September 22 17:39 EDT 2021. Contains 347607 sequences. (Running on oeis4.)