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A135734
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a(n) = prime(n)*prime(n+1)*prime(n+2) - prime(n+3)^2.
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2
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-19, -16, 216, 712, 2070, 3670, 6588, 11712, 19308, 31582, 45178, 63022, 80052, 103632, 143248, 186258, 236092, 284848, 341020, 402568, 470740, 574164, 706338, 861324, 997642, 1101240, 1188520, 1301790, 1547098, 1861212, 2259948, 2472432, 2814606
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OFFSET
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1,1
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COMMENTS
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a(n) > 0 for all n >= 3.
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LINKS
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S. Bulman-Fleming and E. T. H. Wang, Problem 356, College Math. J., 20 (1989), 265.
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FORMULA
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MAPLE
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MATHEMATICA
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Table[Prime[n] Prime[n + 1] Prime[n + 2] - Prime[n + 3]^2, {n, 50}] (* Vincenzo Librandi, Apr 17 2015 *)
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PROG
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(Magma) [NthPrime(n)*NthPrime(n+1)*NthPrime(n+2)-NthPrime(n+3)^2: n in [1..40]]; // Vincenzo Librandi, Apr 17 2015
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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STATUS
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approved
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