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 A188350 Number of arrangements of n+1 numbers x(i) in -1..1 with the sum of x(i)*x(i+1) equal to zero 1
 5, 15, 29, 91, 197, 627, 1477, 4671, 11693, 36487, 95405, 293695, 792525, 2412175, 6660989, 20097243, 56450693, 169229571, 481426405, 1436666475, 4126292293, 12275100443, 35511918037, 105423983379, 306684489749, 909271908483 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 1 of A188358 LINKS R. H. Hardin, Table of n, a(n) for n = 1..200 EXAMPLE Some solutions for n=4 ..1....0....1...-1....0...-1....1....0....1...-1....0....0...-1...-1...-1....0 ..0....0....0....0....0...-1....0....1....1....0....0....0....1....0....0....0 .-1...-1....1....1...-1....1...-1...-1....0...-1...-1...-1....1....0....0....1 .-1....0....0...-1....0....0....0...-1...-1....1....0...-1....0....0...-1....1 ..1....1...-1...-1...-1....1...-1....0....1....1....0....1...-1...-1....0...-1 CROSSREFS Sequence in context: A298025 A162525 A212871 * A268222 A285630 A078905 Adjacent sequences: A188347 A188348 A188349 * A188351 A188352 A188353 KEYWORD nonn AUTHOR R. H. Hardin Mar 28 2011 STATUS approved

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Last modified December 4 08:59 EST 2023. Contains 367558 sequences. (Running on oeis4.)