A121921 A102897(n) - 1.

1, 3, 13, 121, 4959, 2771103, 151947502947

Offset

0,2

Comments

Same as A102897, but counts nonempty set systems.

Links

Table of n, a(n) for n=0..6.

Crossrefs

Sequence in context: A057865 A344210 A260847 * A191955 A241458 A302861

Adjacent sequences: A121918 A121919 A121920 * A121922 A121923 A121924

Keyword

nonn

Author

N. J. A. Sloane, Mar 17 2007

Status

approved