A171872 Triangle read by columns: Distinct classifications of N elements containing exactly R binary partitions.

1, 0, 1, 0, 1, 1, 0, 2, 3, 3, 1, 1, 0, 3, 17, 36, 60, 56, 50, 27, 19, 6, 4, 1, 1, 0, 6, 74, 573, 2802, 10087, 26512, 55088, 91984, 130267, 157662, 168890, 158658, 133576, 98804, 65664, 38073, 19963, 9013, 3779

Offset

0,8

Comments

The bottom of each column is marked by a single 0 in this sequence. Value is 0 for all (N,R) for which N is greater than 2^R.

See note on efficient computation in A171871.

Links

Table of n, a(n) for n=0..44.

R. Munafo, Classifications of N Elements

Crossrefs

First term in each column is A000055(R+1).

Column 4 shares terms with A034189, column 5 with A034190.

Sequence in context: A228624 A124798 A318741 * A005135 A290003 A139460

Adjacent sequences: A171869 A171870 A171871 * A171873 A171874 A171875

Keyword

nonn,tabf

Author

Robert Munafo, Jan 21 2010

Status

approved