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A125292 Numbers having either no ones or no twos in their ternary representation. 6
1, 2, 3, 4, 6, 8, 9, 10, 12, 13, 18, 20, 24, 26, 27, 28, 30, 31, 36, 37, 39, 40, 54, 56, 60, 62, 72, 74, 78, 80, 81, 82, 84, 85, 90, 91, 93, 94, 108, 109, 111, 112, 117, 118, 120, 121, 162, 164, 168, 170, 180, 182, 186, 188, 216, 218, 222, 224, 234, 236, 240, 242, 243 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Complement of A125293; union of A005823 and A005836;

A125291(a(n)) = 1; A062756(a(n))*A081603(a(n)) = 0.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..8190

Eric Weisstein's World of Mathematics, Ternary

Eric Weisstein's World of Mathematics, Repdigit

MATHEMATICA

not[n_]:=Module[{c=DigitCount[n, 3]}, c[[1]]==0||c[[2]]==0]; Select[ Range[ 250], not] (* Harvey P. Dale, Dec 15 2012 *)

PROG

(PARI) is(n, base=3) = #Set(select(sign, digits(n, base)))==1 \\ Rémy Sigrist, Mar 28 2020

(PARI) a(n, base=3) = { for (w=0, oo, if (n<=(base-1)*2^w, my (d=1+(n-1)\2^w, k=2^w+(n-1)%(2^w)); return (d*fromdigits(binary(k), base)), n -= (base-1)*2^w)) } \\ Rémy Sigrist, Mar 28 2020

CROSSREFS

Subsequence of A154314.

Cf. A007089, A125289.

Sequence in context: A026433 A015858 A321473 * A101513 A153276 A298866

Adjacent sequences:  A125289 A125290 A125291 * A125293 A125294 A125295

KEYWORD

nonn,base,easy

AUTHOR

Reinhard Zumkeller, Nov 26 2006

STATUS

approved

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Last modified May 17 00:16 EDT 2021. Contains 343957 sequences. (Running on oeis4.)