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 A121089 Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7. 1

%I

%S 9,24,169,1479,2964,3039,3299,4084,4474,5534,5574,6449,7359,7409,7529,

%T 10789,10879,10994,13819,14324,18574,19709,20329,20749,22179,24529,

%U 25089,25104,25229,25404,27714,27779,29849,30234,32369,33384,34799

%N Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7.

%C Apparently there are no four subsequent numbers m with f(m) prime.

%H Harvey P. Dale, <a href="/A121089/b121089.txt">Table of n, a(n) for n = 1..1000</a>

%t Reap[Do[If[PrimeQ[72*n^2+7]&&PrimeQ[72*(n+1)^2+7]&&PrimeQ[72*(n+2)^2+7],Sow[n]],{n,0,300000}]][[2,1]]

%t Flatten[Position[Partition[Table[PrimeQ[72n^2+7],{n,35000}],3,1],{True,True,True}]] (* _Harvey P. Dale_, Aug 17 2014 *)

%Y Cf. A007522, A121068.

%K nonn

%O 1,1

%A _Zak Seidov_, Aug 11 2006

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Last modified December 13 03:41 EST 2019. Contains 329968 sequences. (Running on oeis4.)