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A330828
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The squares of the Fermat primes, (A019434(n))^2.
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4
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OFFSET
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1,1
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COMMENTS
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Also the first element of the power-spectral basis of A330826. The second element of the power-spectral basis of A330826 is A001146(n+1), n=0..4.
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 3^2 = 9. The spectral basis of A330826(1) = 12 is {9,4}, consisting of primes and powers.
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MAPLE
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F := n -> 2^(2^n) + 1;
a := proc(n) if isprime(F(n)) then return F(n)^2 fi; end;
[seq(a(n)), n=0..4)];
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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_Walter Kehowski_, Jan 06 2020
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STATUS
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approved
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