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 A189771 Number of simple graphs on n nodes that are Euler (all nodes even) but not Eulerian (single cycle passes through all edges). 0
 0, 0, 0, 0, 0, 1, 2, 7, 20, 76, 334, 2498, 36398, 1225629, 89060804, 12978995815, 3646305137905, 1947685504386516, 1969840087225045340, 3770491704215436784514, 13674048211165798257589446, 94122727377410134768239226418 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 COMMENTS There are more Euler graphs than Eulerian graphs since there exist disconnected graphs having multiple disjoint cycles with each node even but for which no single cycle passes through all edges. LINKS Eric Weisstein's World of Mathematics, Euler Graph Eric Weisstein's World of Mathematics, Eulerian Graph FORMULA a(n) = A002854(n) - A133736(n). CROSSREFS Cf. A002854, A133736. Sequence in context: A095268 A118397 A171191 * A260504 A009697 A139012 Adjacent sequences:  A189768 A189769 A189770 * A189772 A189773 A189774 KEYWORD nonn AUTHOR Eric W. Weisstein, Apr 26 2011 STATUS approved

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Last modified March 29 02:19 EDT 2020. Contains 333104 sequences. (Running on oeis4.)