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A004197 Table of min(x,y), where (x,y) = (0,0),(0,1),(1,0),(0,2),(1,1),(2,0),... 11
0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 2, 1, 0, 0, 1, 2, 2, 1, 0, 0, 1, 2, 3, 2, 1, 0, 0, 1, 2, 3, 3, 2, 1, 0, 0, 1, 2, 3, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 6, 6, 5, 4, 3, 2, 1, 0, 0, 1, 2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,13

COMMENTS

Row sums give A002620. - Reinhard Zumkeller, Jul 27 2005

Highest power of 6 that divides A036561. - Fred Daniel Kline, May 29 2012

Triangle T(n,k) read by rows : T(n,k) = min(k,n-k). - Philippe Deléham, Feb 25 2014

LINKS

Reinhard Zumkeller, Rows n=0..100 of triangle, flattened

FORMULA

a(n) = A003983(n) - 1.

G.f.: x*y/((1-x)*(1-y)*(1-x*y)). - Franklin T. Adams-Watters, Feb 06 2006

2^T(n,k) = A144464(n,k), 3^T(n,k) = A152714(n,k), 4^T(n,k) = A152716(n,k), 5^T(n,k) = A152717(n,k). - Philippe Deléham, Feb 25 2014

EXAMPLE

Top left corner of table:

0 0 0 0

0 1 1 1

0 1 2 2

0 1 2 3

Triangle T(n,k) begins:

0;

0, 0;

0, 1, 0;

0, 1, 1, 0;

0, 1, 2, 1, 0;

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

0, 1, 2, 3, 2, 1, 0;

0, 1, 2, 3, 3, 2, 1, 0;

0, 1, 2, 3, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 5, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 5, 6, 5, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 5, 6, 6, 5, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 2, 1, 0;

0, 1, 2, 3, 4, 5, 6, 7, 7, 6, 5, 4, 3, 2, 1, 0;... - Philippe Deléham, Feb 25 2014

MATHEMATICA

Flatten[Table[IntegerExponent[2^(n - k) 3^k, 6], {n, 0, rows}, {k, 0, n}]] (* Fred Daniel Kline, May 29 2012 *)

PROG

(Haskell)

a004197 n k = a004197_tabl !! n !! k

a004197_tabl = map a004197_row [0..]

a004197_row n = hs ++ drop (1 - n `mod` 2) (reverse hs)

   where hs = [0..n `div` 2]

-- Reinhard Zumkeller, Aug 14 2011

(PARI) T(x, y)=min(x, y) \\ Charles R Greathouse IV, Feb 07 2017

CROSSREFS

Cf. A144464, A152714, A152716, A152717.

Similar to but strictly different from A087062 and A261684.

Sequence in context: A015339 A137867 A111143 * A261684 A048571 A025880

Adjacent sequences:  A004194 A004195 A004196 * A004198 A004199 A004200

KEYWORD

tabl,nonn,easy,nice

AUTHOR

David W. Wilson

STATUS

approved

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Last modified October 20 00:50 EDT 2018. Contains 316378 sequences. (Running on oeis4.)