A222808 Number of subsets A of {0,1,...,n-1} with |A+A| < |A-A|.

0, 0, 0, 2, 8, 24, 62, 150, 338, 738, 1568, 3282, 6780, 13904, 28288, 57342, 115812, 233426, 469656, 944000, 1895194, 3802762, 7625328, 15284798, 30626642, 61353084, 122872144, 246042562, 492592948, 986089652, 1973756116, 3950330140, 7905541650, 15819942048, 31655323370

Offset

1,4

Comments

Some authors work with subsets of [0..n-1], others with subsets of [1..n].

Keywords: sum-dominant sets, MSTD sets.

a(1)-a(21) were computed by Daniel C. R. Scheinerman, Mar 10 2013; although a(1)-a(27) had been found by Kevin O'Bryant some time earlier.

Links

James Wilcox and Giovanni Resta, Table of n, a(n) for n = 1..40 (first 35 terms from James Wilcox)

Greg Martin and Kevin O'Bryant, Many sets have more sums than differences, arXiv:math/0608131 [math.NT], 2006.

Crossrefs

Cf. A118544, A140794, A222807.

Sequence in context: A075218 A006728 A234933 * A075216 A127790 A006730

Adjacent sequences: A222805 A222806 A222807 * A222809 A222810 A222811

Keyword

nonn

Author

N. J. A. Sloane, Mar 10 2013

Extensions

a(28)-a(35) from James Wilcox, Jul 22 2013

Status

approved