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A118336
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a(n) = greatest multiple of (p(n+1) - p(n)) which is < p(n), where p(m) is the m-th prime.
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1
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1, 2, 4, 4, 10, 12, 16, 16, 18, 28, 30, 36, 40, 40, 42, 48, 58, 60, 64, 70, 72, 76, 78, 88, 96, 100, 100, 106, 108, 112, 124, 126, 136, 130, 148, 150, 156, 160, 162, 168, 178, 180, 190, 192, 196, 192, 204, 220, 226, 228, 228, 238, 240, 246, 252, 258, 268, 270, 276
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OFFSET
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1,2
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COMMENTS
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A118335(n) - a(n) = 2*(p(n+1) - p(n)). A113709(n) - a(n) = p(n+1) - p(n), for n >= 2.
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LINKS
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FORMULA
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a(1)=1; a(n) = (p(n+1) - p(n))*floor(p(n)/(p(n+1)-p(n))) for n >= 2. - Emeric Deutsch, Apr 27 2006
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MAPLE
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a:=n->(ithprime(n+1)-ithprime(n))*floor(ithprime(n)/(ithprime(n+1)-ithprime(n))): 1, seq(a(n), n=2..64); # Emeric Deutsch, Apr 27 2006
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MATHEMATICA
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Join[{1}, Floor[First[#]/(Last[#]-First[#])](Last[#]-First[#])&/@Partition[Prime[ Range[ 2, 60]], 2, 1]] (* Harvey P. Dale, Feb 25 2013 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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