A174076
Number of permutations of length n with no consecutive triples i,i+2,i+4 or i,i-2,i-4.
Original entry on oeis.org
1, 1, 2, 6, 24, 108, 632, 4408, 35336, 319056, 3205824, 35451984, 427683560, 5588310904, 78615281768, 1184587864512, 19033796498496, 324852522308160, 5868833343451592, 111889157407344424
Offset: 0
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).
A174077
Number of permutations of length n with no consecutive triples i,i+2,i+4 (mod n) or i,i-2,i-4 (mod n).
Original entry on oeis.org
1, 1, 2, 0, 24, 80, 504, 3794, 31616, 290970, 2973600, 33311520, 405781344, 5342413414, 75612197528, 1144942063230, 18471128518656, 316309310084728, 5730646943736936
Offset: 0
As an example, (0,4,1,2,3) is counted by a(5), but (0,4,1,3,2) is not because it has the progression 4,1,3.
A174078
Number of circular permutations of length n with no consecutive triples i,i+2,i+4 or i,i-2,i-4.
Original entry on oeis.org
20, 100, 600, 4244, 34264, 311424, 3143912, 34833964, 420917638, 5513592091, 77715460917
Offset: 5
For n=5 there are (5-1)!-a(5)=4 circular permutations with i,i+2,i+4 or i,i-2,i-4 triples. They are (0,2,4,1,3), (0,2,4,3,1), (0,1,3,4,2), and (0,3,1,4,2).
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