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A039222 Numbers whose base-12 representation has the same number of 1's and 4's. 1
0, 2, 3, 5, 6, 7, 8, 9, 10, 11, 16, 24, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 38, 39, 41, 42, 43, 44, 45, 46, 47, 49, 60, 62, 63, 65, 66, 67, 68, 69, 70, 71, 72, 74, 75, 77, 78, 79, 80, 81, 82, 83, 84, 86, 87, 89, 90, 91, 92, 93, 94, 95, 96, 98, 99, 101, 102, 103, 104 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

filter:= proc(n) local F;

  F:= convert(n, base, 12);

  numboccur(1, F)=numboccur(4, F)

end proc:

select(filter, [$0..200]); # Robert Israel, Apr 15 2019

MATHEMATICA

Select[Range[0, 120], DigitCount[#, 12, 1]==DigitCount[#, 12, 4]&] (* Harvey P. Dale, Mar 12 2018 *)

PROG

(PARI) isok(n) = my(d=digits(n, 12)); #select(x->(x==1), d) == #select(x->(x==4), d); \\ Michel Marcus, Apr 16 2019

CROSSREFS

Sequence in context: A282843 A074137 A206027 * A340745 A183295 A029927

Adjacent sequences:  A039219 A039220 A039221 * A039223 A039224 A039225

KEYWORD

nonn,base,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified November 30 06:28 EST 2021. Contains 349419 sequences. (Running on oeis4.)