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A110423 (n+1)(n+2)...(n+prime(k)) where prime(k) < or = n < prime(k+1). 2
12, 120, 210, 30240, 55440, 17297280, 32432400, 57657600, 98017920, 28158588057600, 53970627110400, 64764752532480000, 124903451312640000, 233153109116928000, 422590010274432000, 830034394580628357120000 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

a(p)=(2p)!/p! if p is a prime.

LINKS

Robert Israel, Table of n, a(n) for n = 2..366

FORMULA

a(n) = (n+A007917(n))!/n!. - Robert Israel, Aug 18 2019

EXAMPLE

a(6) = 7*8*9*10*11 = 55440.

MAPLE

p:=proc(n) if isprime(n)=true then n else prevprime(n) fi end: a:=n->product(n+j, j=1..p(n)): seq(a(n), n=2..19); # p is a modified prevprime command (for n prime yields n rather than the previous prime) # Emeric Deutsch, Aug 07 2005

# Simpler alternative:

seq((n+prevprime(n+1))!/n!, n=2..20); # Robert Israel, Aug 18 2019

CROSSREFS

Cf. A007917, A110424.

Sequence in context: A075366 A276668 A076633 * A006953 A164877 A121032

Adjacent sequences:  A110420 A110421 A110422 * A110424 A110425 A110426

KEYWORD

easy,nonn

AUTHOR

Amarnath Murthy, Aug 01 2005

EXTENSIONS

More terms from Emeric Deutsch, Aug 07 2005

STATUS

approved

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Last modified November 17 00:08 EST 2019. Contains 329209 sequences. (Running on oeis4.)