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A161672 Half the product of all numbers from A141468(n) up to prime(n). 0
0, 3, 10, 21, 3960, 77220, 490089600, 1523733120, 2075793350400, 50710801232931840000, 3144069676441774080000, 19348101737674447004467200000, 137500509682406403378413568000000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

a(n) = prime(n)!/ (2*(A141468(n)-1)!).

EXAMPLE

a(1)=0 is the product 0*1*2/2. a(2) is the product 1*2*3/2 = 3. a(3)=10 is the product 4*5/2.

CROSSREFS

Cf. A000040, A141468.

Sequence in context: A158030 A068082 A058077 * A190092 A174459 A122795

Adjacent sequences:  A161669 A161670 A161671 * A161673 A161674 A161675

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Jun 16 2009

EXTENSIONS

a(0) replaced by 0 - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 21 2010

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.