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A092978 (Product of first n even numbers)/(product of first k odd numbers) where k is chosen to give the least integer. 0
2, 8, 16, 128, 256, 3072, 6144, 98304, 196608, 3932160, 7864320, 188743680, 25165824, 704643072, 21139292160, 676457349120, 1352914698240, 48704929136640, 4638564679680, 185542587187200, 7792788661862400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..21.

FORMULA

For n even, a(n+1)=2*a(n); for n odd, a(n+1)=2(n+1)*a(n). For n even, a(n)=[2^(3n/2)]*(n/2)!; for n odd, a(n)=[2^( (3n-1)/2)]*((n-1)/2)!. - Mark Hudson (mrmarkhudson(AT)hotmail.com), Jul 23 2004

EXAMPLE

a(5) = 256 = (2*4*6*8*10)/(1*3*5) as (2*4*6*8*10)/(1*3*5*7) is not an integer, here k = 3.

CROSSREFS

Sequence in context: A249308 A199043 A046161 * A280777 A013516 A259688

Adjacent sequences:  A092975 A092976 A092977 * A092979 A092980 A092981

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Mar 27 2004

EXTENSIONS

More terms from Mark Hudson (mrmarkhudson(AT)hotmail.com), Jul 23 2004

Corrected and extended by Sam Handler (sam_5_5_5_0(AT)yahoo.com), Oct 23 2004

STATUS

approved

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Last modified October 21 20:51 EDT 2018. Contains 316428 sequences. (Running on oeis4.)