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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 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 FORMULA T(n,k) = A027750(n,k) mod 2, 1 <= k <= A000005(n). T(n,1) = 1; T(n,A000005(n)) = n mod 2. 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 (PARI) row(n) = apply(x->x%2, divisors(n)); \\ Michel Marcus, Jan 23 2022 CROSSREFS Cf. A000005 (row lengths), A001227 (row sums), A183063. Sequence in context: A305994 A030302 A051023 * A030657 A249066 A176178 Adjacent sequences:  A247792 A247793 A247794 * A247796 A247797 A247798 KEYWORD nonn,tabf,changed AUTHOR Reinhard Zumkeller, Sep 28 2014 STATUS approved

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Last modified January 23 16:13 EST 2022. Contains 350514 sequences. (Running on oeis4.)