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 A174076 Number of permutations of length n with no consecutive triples i,i+2,i+4 or i,i-2,i-4. 3
 108, 632, 4408, 35336, 319056 (list; graph; refs; listen; history; text; internal format)
 OFFSET 5,1 COMMENTS Note for n<5 there are no such subsequences, so those values are trivially n!. Also note it is possible for a permutation to have both i,i+2,i+4 and i,i-2,i-4 triples, as in an example from n=7: (2,4,6,5,3,1,0). This permutation is not counted by a(7). LINKS EXAMPLE For n=5 there are 5!-a(5)=12 permutations with i,i+2,i+4 or i,i-2,i-4 triples. An examples of one is (4,2,0,1,3). CROSSREFS Cf. A095816, A174077, A174078, A174079. Sequence in context: A160919 A129027 A204276 * A202194 A203373 A184201 Adjacent sequences:  A174073 A174074 A174075 * A174077 A174078 A174079 KEYWORD nonn AUTHOR Isaac Lambert, Mar 10 2010 STATUS approved

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