A133008 The defining property of the sequences {A, B} = {A000028, A000379} is that they are the unique pair of sets complementary with respect to the positive integers such that p(n) = |{x : x, y in A, x < y, xy = n}| = |{x : x, y in B, x < y, xy = n}| for all n >= 1. The present sequence gives the values of p(n).

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

Offset

1,48

Links

David W. Wilson, Table of n, a(n) for n = 1..10000

Prog

(Haskell)
a133008 n = length [x | x <- takeWhile (< n) a000028_list,
                    n `mod` x == 0, let y = n `div` x, x < y,
                    y `elem` takeWhile (<= n) a000028_list]
-- Reinhard Zumkeller, Oct 05 2011

Crossrefs

Cf. A000028, A000379, A000069, A001969, A133009.

Sequence in context: A353422 A095408 A357375 * A102550 A293139 A351319

Adjacent sequences: A133005 A133006 A133007 * A133009 A133010 A133011

Keyword

nonn

Author

David W. Wilson, Dec 21 2007

Status

approved