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%I
%S 1,10,50,4946,397706,1243141,3445873,9210805,805715770,1542576890
%N Numbers n such that n*prime(n)-1 is a perfect square.
%C Next term, if it exists, is >400000. - 397706 from _Emeric Deutsch_, May 31 2005
%C a(11) > pi(4*10^12). [From _Donovan Johnson_, Oct 22 2010]
%e 1*2-1=1^2
%e 10*29-1=17^2
%e 50*229-1=107^2
%e 4946*47981-1=15405^2
%K nonn
%O 1,2
%A _Zak Seidov_, May 06 2005
%E 397706 from _Emeric Deutsch_, May 31 2005
%E 4 more terms from Ryan Propper (rpropper(AT)stanford.edu), Oct 16 2005
%E a(10) from _Donovan Johnson_, Oct 22 2010
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