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A219463 Triangle read by rows: T(n,k) = 1 - A047999(n,k), 0 <= k <= n. 5
0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0

COMMENTS

Sierpinski's triangle complemented.

LINKS

Reinhard Zumkeller, Rows n = 0..128 of triangle, flattened

Eric Weisstein's World of Mathematics, Sierpinski Sieve

Wikipedia, Sierpinski triangle

Index entries for triangles and arrays related to Pascal's triangle

FORMULA

T(n,k) = if T(n-1,k-1) = T(n-1,k) then 1 else 0, 0 < k < n.

EXAMPLE

The triangle begins:

.   0:                                0

.   1:                              0   0

.   2:                            0   1   0

.   3:                          0   0   0   0

.   4:                        0   1   1   1   0

.   5:                      0   0   1   1   0   0

.   6:                    0   1   0   1   0   1   0

.   7:                  0   0   0   0   0   0   0   0

.   8:                0   1   1   1   1   1   1   1   0

.   9:              0   0   1   1   1   1   1   1   0   0

.  10:            0   1   0   1   1   1   1   1   0   1   0

.  11:          0   0   0   0   1   1   1   1   0   0   0   0

.  12:        0   1   1   1   0   1   1   1   0   1   1   1   0

.  13:      0   0   1   1   0   0   1   1   0   0   1   1   0   0

.  14:    0   1   0   1   0   1   0   1   0   1   0   1   0   1   0

.  15:  0   0   0   0   0   0   0   0   0   0   0   0   0   0   0   0 .

PROG

(Haskell)

a219463 n k = a219463_tabl !! n !! k :: Int

a219463_row n = a219463_tabl !! n

a219463_tabl = map (map (1 -)) a047999_tabl

CROSSREFS

Cf. A000004 (left and right edges), A057427 (central terms), A048967 (row sums = number of ones per row), A001316 (number of zeros per row), A219843 (rows as binary numbers).

Sequence in context: A288665 A316345 A236192 * A286688 A285125 A221152

Adjacent sequences:  A219460 A219461 A219462 * A219464 A219465 A219466

KEYWORD

nonn,tabl

AUTHOR

Reinhard Zumkeller, Nov 30 2012

STATUS

approved

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Last modified October 20 15:44 EDT 2018. Contains 316389 sequences. (Running on oeis4.)