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A108570 Squares of the form prime(n)*prime(n+1) - 2*prime(n). 4

%I

%S 9,25,121,289,841,1681,3481,5041,10201,11449,18769,22201,32041,36481,

%T 38809,51529,57121,72361,78961,96721,120409,175561,185761,212521,

%U 271441,323761,358801,380689,410881,434281,654481,674041,683929,734449,776161

%N Squares of the form prime(n)*prime(n+1) - 2*prime(n).

%C Squares of lesser of twin primes.

%p ZL:=[]:for p from 1 to 950 do if (isprime(p) and isprime(p+2)) then ZL:=[op(ZL),(p^2)]; fi; od; print(ZL); # _Zerinvary Lajos_, Mar 08 2007

%t Select[First[#]Last[#]-2First[#]&/@Partition[Prime[Range[500]],2,1],IntegerQ[ Sqrt[#]]&] (* _Harvey P. Dale_, May 24 2011 *)

%Y Cf. A001359, A108604.

%K easy,nonn

%O 1,1

%A _Giovanni Teofilatto_, Jul 05 2005

%E Extended by _Ray Chandler_, Jul 10 2005

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Last modified May 23 11:20 EDT 2019. Contains 323514 sequences. (Running on oeis4.)