A179957 Number of permutations of 1..n such that |p(i)-p(i-1)|>= 4 for i>1.

1, 1, 0, 0, 0, 0, 0, 0, 2, 72, 1496, 25384, 399848, 6231544, 99133496, 1634227958, 28120703888, 506599465896, 9562489659952, 189055933191880, 3911226769004280, 84567966329357056

Offset: 0

Author

R. H. Hardin, Aug 03 2010

Keywords

• nonn

Extensions

a(0), a(19)-a(20) from Alois P. Heinz, Oct 27 2014

a(21) from Alois P. Heinz, Feb 10 2025