login
A059420
A diagonal of A059419.
3
1, 20, 616, 28160, 1805056, 154918400, 17171485696, 2389096202240, 407776690241536, 83793407533383680, 20407552701432856576, 5813146553630295326720, 1914890082050142493474816
OFFSET
1,2
REFERENCES
L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 259.
FORMULA
a(n)= A059419(2*n+1, 3). From the expansion of tan(x)^3/6.
CROSSREFS
Cf. A059419.
Sequence in context: A035279 A015268 A202577 * A129906 A125722 A336412
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jan 30 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), Feb 08 2001. Corrected and extended by Wolfdieter Lang, Feb 09 2001.
STATUS
approved