A171075 Total number of balls on lawn in variant of the tennis ball problem (cf. A171074);

1, 20, 190, 1226, 6878, 35962, 180080

Offset

1,2

Comments

Apparently equals A051133(n) - A005893(n) after 1st term.

Note that A051133 yields the totals of all C(2n, n) ball sets and A005893 and A090288 are the respective totals of impossible combinations given the rules.

References

David Scambler, Just for fun, more tennis balls, Posting to the Sequence Fans Mailing List, Aug 25 2010.

Links

Table of n, a(n) for n=1..7.

Crossrefs

Sequence in context: A010936 A014806 A022615 * A061180 A125383 A126541

Adjacent sequences: A171072 A171073 A171074 * A171076 A171077 A171078

Keyword

nonn

Author

N. J. A. Sloane, Sep 06 2010

Status

approved