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A207830 Positive multiples of 3 that contain the decimal digit 1. 0
12, 15, 18, 21, 51, 81, 102, 105, 108, 111, 114, 117, 120, 123, 126, 129, 132, 135, 138, 141, 144, 147, 150, 153, 156, 159, 162, 165, 168, 171, 174, 177, 180, 183, 186, 189, 192, 195, 198, 201, 210, 213, 216, 219, 231, 261, 291, 312, 315, 318, 321, 351, 381, 411, 414 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

I came across this sequence while working some problems in ALCUMUS from the AoPS site. [Tyler]

A 10-automatic set: members are numbers with decimal expansions matching a regular expression. - Charles R Greathouse IV, Feb 20 2012

REFERENCES

MathCounts 2006 National Target #5

LINKS

Table of n, a(n) for n=1..55.

Index entries for 10-automatic sequences.

MATHEMATICA

Select[3*Range[138], DigitCount[#, 10, 1] > 0 &] (* Alonso del Arte, Feb 20 2012 *)

PROG

(PARI) is(n)=if(n%3, return(0)); n=vecsort(eval(Vec(Str(n))), , 8); n[1]==1||(#n>1&&n[2]==1) \\ Charles R Greathouse IV, Feb 20 2012

(PARI) is(n)=n%3==0 && setsearch(Set(digits(n)), 1) \\ Charles R Greathouse IV, Feb 12 2017

CROSSREFS

Sequence in context: A265128 A243021 A164782 * A101171 A329731 A120169

Adjacent sequences:  A207827 A207828 A207829 * A207831 A207832 A207833

KEYWORD

nonn,base,easy

AUTHOR

Seth Tyler, Feb 20 2012

EXTENSIONS

a(7)-a(55) from Charles R Greathouse IV, Feb 20 2012

STATUS

approved

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Last modified June 17 19:32 EDT 2021. Contains 345085 sequences. (Running on oeis4.)