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a(n) = prime(n)*prime(n+1)*prime(n+2) - prime(n+3)^2.
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%I #23 Dec 11 2022 16:17:04

%S -19,-16,216,712,2070,3670,6588,11712,19308,31582,45178,63022,80052,

%T 103632,143248,186258,236092,284848,341020,402568,470740,574164,

%U 706338,861324,997642,1101240,1188520,1301790,1547098,1861212,2259948,2472432,2814606

%N a(n) = prime(n)*prime(n+1)*prime(n+2) - prime(n+3)^2.

%C a(n) > 0 for all n >= 3.

%H G. C. Greubel, <a href="/A135734/b135734.txt">Table of n, a(n) for n = 1..1000</a>

%H S. Bulman-Fleming and E. T. H. Wang, <a href="http://www.jstor.org/stable/2686778">Problem 356</a>, College Math. J., 20 (1989), 265.

%F a(n) = A046301(n) - A001248(n+3). - _R. J. Mathar_, Mar 06 2008 [Corrected by _Georg Fischer_, Dec 11 2022]

%p A135734:=n->ithprime(n)*ithprime(n+1)*ithprime(n+2)-ithprime(n+3)^2: seq(A135734(n), n=1..50); # _Wesley Ivan Hurt_, Oct 05 2017

%t Table[Prime[n] Prime[n + 1] Prime[n + 2] - Prime[n + 3]^2, {n, 50}] (* _Vincenzo Librandi_, Apr 17 2015 *)

%o (Magma) [NthPrime(n)*NthPrime(n+1)*NthPrime(n+2)-NthPrime(n+3)^2: n in [1..40]]; // _Vincenzo Librandi_, Apr 17 2015

%Y Cf. A001248, A046301.

%K sign,easy

%O 1,1

%A _N. J. A. Sloane_, Mar 05 2008