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A059420 A diagonal of A059419. 3
1, 20, 616, 28160, 1805056, 154918400, 17171485696, 2389096202240, 407776690241536, 83793407533383680, 20407552701432856576, 5813146553630295326720, 1914890082050142493474816 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 259.

LINKS

Table of n, a(n) for n=1..13.

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 A226731

Adjacent sequences:  A059417 A059418 A059419 * A059421 A059422 A059423

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

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Last modified January 19 03:38 EST 2019. Contains 319283 sequences. (Running on oeis4.)