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Search: id:A073836
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| A073836 |
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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)]. |
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+0
1
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| 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
(list; graph; listen)
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OFFSET
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1,2
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EXAMPLE
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a(4)= Floor[14*15*16/12] =280.
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MATHEMATICA
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c[n_] := Times @@ Select[Range[Prime[n], Prime[n + 1]], PrimeQ[ # ]==False&]; Table[Floor[c[n + 1]/c[n]], {n, 2, 30}] - Ryan Propper (rpropper(AT)stanford.edu), Jul 21 2006
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PROGRAM
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(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
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CROSSREFS
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Sequence in context: A020529 A069328 A020546 this_sequence A090217 A062829 A062690
Adjacent sequences: A073833 A073834 A073835 this_sequence A073837 A073838 A073839
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KEYWORD
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nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 12 2002
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EXTENSIONS
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More terms from Ryan Propper (rpropper(AT)stanford.edu), Jul 21 2006
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 02 2007
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