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A068556 From numerators in expansion of tan(arcsinh(x)) - sin(arctanh(x)). 1
0, 0, 0, 0, 4, 4, 377, 1202, 133211, 1082357, 3730351411, 6203235575, 28719995819965, 2124563380903465, 122827509141846335, 42344667805954043, 1305035883448960477, 36723101348641621053659, 384279850938174722635253, 71260765129276904394438865 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

REFERENCES

R. W. Gosper, personal communication, Mar 07, 2002, who asks if the coefficients are always nonnegative.

LINKS

Table of n, a(n) for n=0..19.

EXAMPLE

4/189*x^8+4/189*x^10+377/12474*x^12+1202/43659*x^14+...

CROSSREFS

Cf. A068557.

Sequence in context: A218050 A107052 A000790 * A078243 A024246 A024247

Adjacent sequences:  A068553 A068554 A068555 * A068557 A068558 A068559

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane, Mar 23 2002

STATUS

approved

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Last modified October 18 23:39 EDT 2019. Contains 328211 sequences. (Running on oeis4.)