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A108091 Coefficients of series whose 8th power is the theta series of E_8 (see A004009). 3
1, 30, -2880, 416640, -69178110, 12378401280, -2321610157440, 449733567736320, -89200812128140800, 18013245273252679710, -3689479088922151082880, 764375901202388789804160, -159862757100127037505991680, 33699694000689939789618455040, -7152050326608893289997995966720, 1526705794390267864554876727856640 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

N. J. A. Sloane, Seven Staggering Sequences, in Homage to a Pied Puzzler, E. Pegg Jr., A. H. Schoen and T. Rodgers (editors), A. K. Peters, Wellesley, MA, 2009, pp. 93-110.

LINKS

Table of n, a(n) for n=0..15.

N. Heninger, E. M. Rains and N. J. A. Sloane, On the Integrality of n-th Roots of Generating Functions, J. Combinatorial Theory, Series A, 113 (2006), 1732-1745.

N. J. A. Sloane, Seven Staggering Sequences.

EXAMPLE

More precisely, the theta series of E_8 begins 1 + 240*q^2 + 2160*q^4 + 6720*q^6 + 17520*q^8 + ... and the 8th root of this is 1 + 30*q^2 - 2880*q^4 + 416640*q^6 - 69178110*q^8 + ...

CROSSREFS

Cf. A004009.

Sequence in context: A061162 A138916 A091544 * A036363 A001459 A209788

Adjacent sequences:  A108088 A108089 A108090 * A108092 A108093 A108094

KEYWORD

sign

AUTHOR

N. J. A. Sloane and Michael Somos, Jun 06 2005

STATUS

approved

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Last modified May 24 11:56 EDT 2013. Contains 225620 sequences.