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A247795 Table read by rows: n-th row = parities of divisors of n. 6
1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

COMMENTS

T(n,k) = A027750(n,k) mod 2, 1 <= k <= A000005(n);

T(n,1) = 1; T(n,A000005(n)) = n mod 2;

A001227(n) = number of ones in row n;

A183063(n) = number of zeros in row n.

LINKS

Reinhard Zumkeller, Rows n = 1..1000 of triangle, flattened

EXAMPLE

.   n |  T(n,*)            |  A027750(n,*)           |  A000005(n)

.  ---+--------------------+-------------------------+------------

.   1 |  1                 |  1                      |        1

.   2 |  1  0              |  1   2                  |        2

.   3 |  1  1              |  1   3                  |        2

.   4 |  1  0  0           |  1   2   4              |        3

.   5 |  1  1              |  1   5                  |        2

.   6 |  1  0  1  0        |  1   2   3   6          |        4

.   7 |  1  1              |  1   7                  |        2

.   8 |  1  0  0  0        |  1   2   4   8          |        4

.   9 |  1  1  1           |  1   3   9              |        3

.  10 |  1  0  1  0        |  1   2   5  10          |        4

.  11 |  1  1              |  1  11                  |        2

.  12 |  1  0  1  0  0  0  |  1   2   3   4   6  12  |        6

.  13 |  1  1              |  1  13                  |        2

.  14 |  1  0  1  0        |  1   2   7  14          |        4

.  15 |  1  1  1  1        |  1   3   5  15          |        4

.  16 |  1  0  0  0  0     |  1   2   4   8  16      |        5

.  17 |  1  1              |  1  17                  |        2

.  18 |  1  0  1  0  1  0  |  1   2   3   6   9  18  |        6

.  19 |  1  1              |  1  19                  |        2

.  20 |  1  0  0  1  0  0  |  1   2   4   5  10  20  |        6  .

PROG

(Haskell)

a247795 n k = a247795_tabf !! (n-1) !! (k-1)

a247795_row n = a247795_tabf !! (n-1)

a247795_tabf = map (map (flip mod 2)) a027750_tabf

CROSSREFS

Cf. A000005 (row lengths), A001227 (row sums), A183063.

Sequence in context: A285431 A267621 A305994 * A267778 A285384 A030324

Adjacent sequences:  A247792 A247793 A247794 * A247796 A247797 A247798

KEYWORD

nonn,tabf

AUTHOR

Reinhard Zumkeller, Sep 28 2014

STATUS

approved

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Last modified October 16 12:00 EDT 2018. Contains 316263 sequences. (Running on oeis4.)