OFFSET
1,1
COMMENTS
FORMULA
EXAMPLE
a(2) = 2^2*(2^2+1) = 20, and the spectral basis of 20 is {5,16}, consisting of primes and powers.
MAPLE
F := n -> 2^(2^n)+1;
a := proc(n) if isprime(F(n)) then return 2^(2^n)*F(n) fi; end;
[seq(a(n), n=0..4)];
CROSSREFS
KEYWORD
nonn
AUTHOR
Walter Kehowski, Jan 06 2020
STATUS
approved