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A180267 Prime(2*n+1)!/(60*prime(2*n-1)!). 1
1, 5544, 148512, 1211364, 5301223200, 67804092195840, 128850876, 8937268342895692800, 4383026968320, 2042765424, 147107459292393600, 40633707301699873935974400, 17158084020, 24300280368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Oscillating sequence

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(3)=prime(7)!/prime(5)!/60=355687428096000/39916800/60=148512

MATHEMATICA

#[[2]]/(60*#[[1]])&/@Partition[Prime[Range[1, 31, 2]]!, 2, 1] (* Harvey P. Dale, Mar 05 2017 *)

PROG

(PARI) a(n)=prime(2*n+1)!/prime(2*n-1)!/60

CROSSREFS

Cf. A178614

Sequence in context: A278012 A255100 A031795 * A203336 A045104 A043512

Adjacent sequences:  A180264 A180265 A180266 * A180268 A180269 A180270

KEYWORD

easy,nonn

AUTHOR

Graziano Aglietti (mg5055(AT)mclink.it), Aug 23 2010

STATUS

approved

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Last modified May 11 21:35 EDT 2021. Contains 343808 sequences. (Running on oeis4.)