A112101 Number of interval orders of magnitude n having no duplicate holdings (NODH).

1, 3, 10, 58, 722, 19826, 1161882, 141436842, 35192653666, 17733070720738, 17997787816364330, 36678689328450847514, 149831453090755680149490, 1225618861520566592060441682, 20064594684596858150355969600442, 657195622713393693107201875915723402

Offset

0,2

References

W. T. Trotter, Combinatorics and Partially Ordered Sets, Johns Hopkins, 1992; see p. 195.

Links

Table of n, a(n) for n=0..15.

Formula

a(n) = Sum_{k=0..n} binomial(n, k)*A111491(k).

Crossrefs

Sequence in context: A274585 A333031 A242953 * A159321 A181077 A158873

Adjacent sequences: A112098 A112099 A112100 * A112102 A112103 A112104

Keyword

nonn

Author

N. J. A. Sloane, Nov 28 2005

Status

approved