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%I #3 Mar 30 2012 18:40:49
%S 727,5623,21611,131771,751691,8311687,16867447,25431851,71014331,
%T 109056251,350550731,3170478247,4435959611,4678970407,6353205851,
%U 9659548091,11977770247,26525659687,29365277771,39262233611,52986054967
%N Primes of the form 9*(p^4)-2 or 9*(p^4)+2, arising in Paley-Hadamard difference sets.
%C Polhill is able to construct Paley-Hadamard difference sets of the Stanton-Sprott family in groups of the form (Z_3)^2 X (Z_p)^4t X (Z_(9p^4t)+2 or -2 when 9*(p^4t)-2 or 9*(p^4t)+2 is a prime power. In this sequence, we are taking just the t=1 case, a prime power as first power of prime.
%D John Bowen Polhill, Paley partial difference sets in groups with order not a prime power, 1046th Meeting of the AMS, Washington, DC, January 5-8, 2009.
%e a(1) = 9*(3^4) - 2 = 727 is prime. a(2) = 9*(5^4) - 2 = 5623 is prime. a(3) = 9*(7^4) + 2 = 21611. a(4) = 9*(11^4) + 2 = 131771. a(5) = 9*(17^4) + 2 = 751691. a(6) = 9*(31^4) - 2 = 8311687. a(7) = 9*(37^4) - 2 = 16867447. a(8) = 9*(41^4) + 2 = 25431851.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Mar 01 2009
%E More terms from _R. J. Mathar_, Mar 06 2009