A066222 - OEIS

A066222

Bisection of A001189.

1, 9, 75, 763, 9495, 140151, 2390479, 46206735, 997313823, 23758664095, 618884638911, 17492190577599, 532985208200575, 17411277367391103, 606917269909048575, 22481059424730751231, 881687990282453393919

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OFFSET

0,2

COMMENTS

a(n) is the number of sets of disjoint pairs that can be chosen from 2*n items. - Ron Zeno (rzeno(AT)hotmail.com), Feb 06 2002

LINKS

Table of n, a(n) for n=0..16.

CROSSREFS

Sequence in context: A231592 A335345 A126965 * A080254 A190916 A161736

Adjacent sequences: A066219 A066220 A066221 * A066223 A066224 A066225

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Dec 19 2001

EXTENSIONS

More terms from Frank Ellermann, Jan 01 2002

STATUS

approved