A030341 - OEIS

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A030341

Triangle T(n,k): write n in base 3, reverse order of digits.

0, 1, 2, 0, 1, 1, 1, 2, 1, 0, 2, 1, 2, 2, 2, 0, 0, 1, 1, 0, 1, 2, 0, 1, 0, 1, 1, 1, 1, 1, 2, 1, 1, 0, 2, 1, 1, 2, 1, 2, 2, 1, 0, 0, 2, 1, 0, 2, 2, 0, 2, 0, 1, 2, 1, 1, 2, 2, 1, 2, 0, 2, 2, 1, 2, 2, 2, 2, 2, 0, 0, 0, 1, 1, 0, 0, 1, 2, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 2, 1, 0, 1

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Reinhard Zumkeller, Rows n = 0..1000 of triangle, flattened

Eric Weisstein's World of Mathematics, Ternary.

Wikipedia, Ternary numeral system

EXAMPLE

Triangle begins :

0, 1

1, 1

2, 1

0, 2

1, 2

2, 2

0, 0, 1

1, 0, 1

2, 0, 1

0, 1, 1

1, 1, 1

2, 1, 1 ...

MAPLE

A030341_row := n -> op(convert(n, base, 3)):

seq(A030341_row(n), n=0..32); # Peter Luschny, Nov 28 2017

MATHEMATICA

Flatten[Table[Reverse[IntegerDigits[n, 3]], {n, 0, 40}]] (* Harvey P. Dale, Oct 20 2014 *)

PROG

(Haskell)

a030341 n k = a030341_tabf !! n !! k

a030341_row n = a030341_tabf !! n

a030341_tabf = iterate succ [0] where

succ [] = [1]

succ (2:ts) = 0 : succ ts

succ (t:ts) = (t + 1) : ts

-- Reinhard Zumkeller, Feb 21 2013

(PARI) A030341(n, k=-1)=/*k<0&&error("Flattened sequence not yet implemented.")*/n\3^k%3 \\ Assuming that columns are numbered starting with k=0 as in A030308, A030567 and others. - M. F. Hasler, Jul 21 2013

CROSSREFS

Cf. A081604 (row lengths), A053735 (row sums), A007089, A003137.

Cf. A030308, A030386, A031235, A030567, A031007, A031045, A031087, A031298 for the base-2 to base-10 analogs.

Sequence in context: A280634 A281491 A099494 * A258832 A121444 A118230

Adjacent sequences: A030338 A030339 A030340 * A030342 A030343 A030344

KEYWORD

nonn,base,tabf,less

AUTHOR

Clark Kimberling

EXTENSIONS

Initial 0 and better name by Philippe Deléham, Oct 20 2011

STATUS

approved