A178009 Number of permutations of 1..n with no element e[i>=2]

1, 1, 1, 2, 6, 24, 60, 240, 1260, 8064, 36288, 241920, 1995840, 19160064, 124540416, 1162377216, 13076743680, 167382319104, 1422749712384, 17072996548608, 243290200817664, 3892643213082624, 34060628114472960, 428190753439088640, 6463004184721244160

Offset: 0

Author

R. H. Hardin, May 17 2010

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..491
• Wikipedia, D-ary heap

Crossrefs

Simple 2-way heap A056971.

Column k=4 of A273693.

Extensions

a(0), a(20)-a(24) from Alois P. Heinz, May 27 2016