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A066515
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Numbers n such that prime(n+1) + prime(n-2) = 2*prime(n-1), where prime(m) is the m-th prime.
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1
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13, 20, 60, 93, 113, 116, 141, 212, 234, 254, 262, 269, 277, 286, 292, 295, 302, 323, 353, 359, 370, 390, 408, 418, 474, 501, 543, 599, 613, 625, 715, 719, 724, 743, 820, 934, 940, 995, 999, 1017, 1099, 1120, 1264, 1300, 1313, 1401, 1415, 1419, 1423
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OFFSET
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1,1
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COMMENTS
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Equivalently, n such that f(n) = f(n-2) - f(n-1) where f is the prime gap function given by f(m) = p(m+1) - p(m).
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LINKS
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MATHEMATICA
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Select[ Range[ 3, 1440 ], Prime[ #+1 ]+Prime[ #-2 ]==2Prime[ #-1 ]& ]
PrimePi[#[[3]]]&/@Select[Partition[Prime[Range[1500]], 4, 1], First[#]+ Last[#]==2#[[2]]&] (* Harvey P. Dale, Apr 13 2012 *)
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PROG
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(PARI) { n=0; for (m=3, 10^10, if (prime(m+1) + prime(m-2) == 2*prime(m-1), write("b066515.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 20 2010
(PARI) isok(n) = prime(n+1) + prime(n-2) == 2*prime(n-1); \\ Michel Marcus, Jan 04 2016
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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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