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%I #10 Jan 07 2020 22:54:16
%S 64,2304,921600,260112384,4501400872550400,295138898048817561600,
%T 75557287266261531623424
%N Numbers of the form (M_p^2-1)^2, where M_p is a Mersenne prime, A000668. Also the second element of the power-spectral basis of A330817.
%C The first element of the power-spectral basis of A330817 is A330819.
%F a(n) = (A000668(n)^2-1)^2.
%e If n=1, a(1)=(3^2-1)^2=64.
%p A330820:=[]:
%p for www to 1 do
%p for i from 1 to 31 do
%p #ithprime(31)=127
%p p:=ithprime(i);
%p q:=2^p-1;
%p if isprime(q) then x:=(q^2-1)^2; A330820:=[op(A330820),x] fi;
%p od;
%p od;
%p A330820;
%t Array[((2^MersennePrimeExponent[#] - 1)^2 - 1)^2 &, 10] (* _Amiram Eldar_, Jan 07 2020 *)
%Y Cf. A000043, A000668, A330817, A330818, A330819.
%K nonn
%O 1,1
%A _Walter Kehowski_, Jan 06 2020
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