A249686 After A084937(n) has been computed, let m = largest term so far in A084937. Then a(n) = number of positive integers < m that are missing from A084937 at this point.

0, 0, 0, 1, 0, 1, 2, 1, 2, 3, 2, 5, 6, 5, 6, 7, 6, 5, 10, 9, 8, 7, 6, 7, 10, 9, 10, 13, 12, 13, 16, 15, 14, 15, 14, 13, 16, 15, 14, 15, 14, 13, 16, 15, 16, 17, 16, 17, 16, 15, 16, 17, 16, 17, 18, 17, 20, 21, 20, 23, 28, 27, 26, 27, 26, 25, 30, 29, 28, 27, 26, 25, 28

Offset

1,7

Comments

Running count of missing numbers in A084937.

It appears that at any point, the number of missing even numbers from A084937 is always much larger than the number of missing odd numbers. It would be nice to have a more precise statement of this property.

In this regard, it would be helpful to have two further sequences, one giving the number of even missing numbers at each point, the other giving the number of odd missing numbers. These are now A250099, A250100. See also A249777, A249856, A249867.

Links

N. J. A. Sloane, Table of n, a(n) for n = 1..100000

Example

After step 7 of A084937, here is what we have:
1 2 3 4 5 6 7 ... n
1 2 3 5 4 7 9 ... A084937(n)
so m = 9, and the missing numbers < 9 are 6 and 8, so a(7) = 2.

Crossrefs

Cf. A084937, A250099, A250100. See A249777, A249856, A249857, A249858 for another way of looking at this question.

Sequence in context: A288126 A214720 A035368 * A107853 A054758 A077876

Adjacent sequences: A249683 A249684 A249685 * A249687 A249688 A249689

Keyword

nonn

Author

N. J. A. Sloane, Nov 05 2014

Status

approved