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A073271
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a(n) = floor( prime(n)*prime(n+2) / prime(n+1) ).
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5
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3, 4, 7, 8, 14, 14, 20, 23, 24, 34, 34, 38, 44, 48, 52, 54, 64, 64, 68, 76, 76, 84, 90, 92, 98, 104, 104, 110, 122, 116, 132, 132, 146, 140, 154, 156, 160, 168, 172, 174, 188, 182, 194, 194, 208, 210, 214, 224, 230, 234, 234, 248, 246, 256, 262, 264, 274, 274
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OFFSET
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1,1
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COMMENTS
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Conjecture: a(n) is even except for a(1)=3, a(3)=7 and a(8)=23 (A073272(n)=0).
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LINKS
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EXAMPLE
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MATHEMATICA
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Table[Floor[Prime[n] Prime[n + 2] / Prime[n + 1]], {n, 60}] (* Vincenzo Librandi, May 31 2015 *)
Floor[(#[[1]]#[[3]])/#[[2]]]&/@Partition[Prime[Range[60]], 3, 1] (* Harvey P. Dale, Jun 07 2021 *)
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PROG
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(PARI) vector(100, n, (prime(n)*prime(n+2))\prime(n+1)) \\ Michel Marcus, May 31 2015
(Magma) [Floor(NthPrime(n)*NthPrime(n+2) / NthPrime(n+1)): n in [1..60]]; // Vincenzo Librandi, May 31 2015
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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