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A084253 a(n) is the denominator of the coefficient of z^(2n-1) in the Maclaurin expansion of Sqrt[Pi]Erfi[z]. 0
1, 3, 5, 21, 108, 660, 4680, 37800, 342720, 3447360, 38102400, 459043200, 5987520000, 84064780800, 1264085222400, 20268952704000, 345226033152000, 6224529991680000, 118443913555968000, 2372079457972224000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Numerators are unity for n>2.

Same as A007680/2 for n>2.

LINKS

Eric Weisstein's World of Mathematics, Erfi

FORMULA

a(n)=(2n-1)(n-1)!/2 for n>2.

CROSSREFS

Cf. A007680.

Sequence in context: A196418 A189560 A179265 * A153889 A186751 A147442

Adjacent sequences:  A084250 A084251 A084252 * A084254 A084255 A084256

KEYWORD

nonn,easy

AUTHOR

Eric Weisstein (eric(AT)weisstein.com), May 23, 2003

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Last modified February 16 10:39 EST 2012. Contains 205904 sequences.