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A118544
Number of subsets A of {1,2,...,n} with |A+A| = |A-A|.
6
2, 4, 8, 14, 24, 40, 66, 106, 174, 286, 480, 814, 1412, 2480, 4476, 8184, 15230, 28652, 54488, 104262, 201266, 390090, 760234, 1486030, 2914492, 5728506, 11289420, 22279222, 44046072, 87181188, 172777354, 342724456, 680524908, 1352154964, 2688763324
OFFSET
1,1
COMMENTS
Keywords: sum-dominant sets, MSTD sets.
Some authors work with subsets of [0..n-1], others with subsets of [1..n].
LINKS
James Wilcox and Giovanni Resta, Table of n, a(n) for n = 1..40 (first 35 terms from James Wilcox)
EXAMPLE
a(4)=14: two of the sixteen subsets of {1,2,3,4} have |A+A|<|A-A| (specifically, {1,3,4} and {1,2,4}).
CROSSREFS
KEYWORD
nonn
AUTHOR
Kevin O'Bryant, May 07 2006
EXTENSIONS
a(21)-a(29) from Robert Gerbicz, Nov 19 2010
a(30)-a(35) from James Wilcox, Jul 22 2013
STATUS
approved