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%I #9 Nov 06 2013 13:12:29
%S 3,2,3,97,241,241,1201,3361,5569,61441,240769,915049,240769,17302321,
%T 7076521,49186201,2100735289,1074527281,23971813321,32354445841,
%U 68820869329,2992426816129,26238323995129,104071698229321
%N a(n) = smallest positive prime number of the form x^2 - n! (where x is a positive integer).
%C For smallest positive integers x see A143931. Prime x see A143933.
%e a(1)=3 because 2^2 - 1! = 3;
%e a(2)=2 because 2^2 - 2! = 2;
%e a(3)=3 because 3^2 - 3! = 3;
%e a(4)=97 because 11^2 - 4! = 97.
%t b = {}; Do[k = Round[Sqrt[n! ]] + 1; While[ ! PrimeQ[k^2 - n! ], k++ ]; AppendTo[b, k^2-n! ], {n, 1, 50}]; b
%Y Cf. A121926, A143931, A143933.
%K nonn
%O 1,1
%A _Artur Jasinski_, Sep 05 2008