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 A078603 Number of ways of arranging the numbers 1..n in a circle so that adjacent numbers do not differ by 1 mod n. 3
 1, 0, 0, 0, 2, 6, 46, 354, 3106, 29926, 315862, 3628906, 45132474, 604534846, 8680957902, 133082437730, 2169964347282, 37505486702678, 685046187718022, 13186335387855770, 266816610979894058, 5662225862272325550 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 LINKS FORMULA See A002816. EXAMPLE a(5) = 2: 1 3 5 2 4, 1 4 2 5 3; a(6) = 6: 1 4 6 2 5 3, 1 5 2 4 6 3, 1 5 3 6 2 4, 1 3 6 4 2 5, 1 4 2 6 3 5, 1 3 5 2 6 4. CROSSREFS Twice A002816. The sequence n*a(n) is A089222. See also A078628. Sequence in context: A136557 A092662 A052811 * A316073 A001587 A306784 Adjacent sequences:  A078600 A078601 A078602 * A078604 A078605 A078606 KEYWORD nonn AUTHOR N. J. A. Sloane, Dec 11 2002 EXTENSIONS The sequence was missing a zero; also added a cross-reference Joel B. Lewis, Jan 28 2010 STATUS approved

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Last modified July 19 12:49 EDT 2019. Contains 325159 sequences. (Running on oeis4.)