A073836 Let C(n) = product of composite numbers between the n-th prime and (n+1)-th prime; a(n) = floor(C(n+1)/C(n)).

1, 120, 0, 280, 0, 513, 1276, 0, 1507968, 0, 0, 2168, 3424, 1, 0, 17873856, 0, 0, 35185150, 0, 8847, 12778, 0, 0, 11348, 0, 12662, 777455654403407438918, 0, 20121, 0, 192643714695223095, 0, 577325548, 1, 0, 31603, 1, 0, 1478997122921398080, 0

Offset

1,2

Links

Table of n, a(n) for n=1..41.

Example

a(4) = floor(14*15*16/12) = 280.

Mathematica

c[n_] := Times @@ Select[Range[Prime[n], Prime[n + 1]], PrimeQ[ # ]==False&]; Table[Floor[c[n + 1]/c[n]], {n, 2, 30}] (* Ryan Propper, Jul 21 2006 *)

Prog

(PARI) C=4; for(n=3, 100, Cp1=1; for(k=prime(n)+1, prime(n+1)-1, Cp1*=k); print1(floor(Cp1/C)", "); C=Cp1) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), May 02 2007

Crossrefs

Sequence in context: A267335 A357968 A156415 * A242836 A229031 A221406

Adjacent sequences: A073833 A073834 A073835 * A073837 A073838 A073839

Keyword

nonn

Author

Amarnath Murthy, Aug 12 2002

Extensions

More terms from Ryan Propper, Jul 21 2006

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 02 2007

Status

approved