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A226484 Odd numbers not of the form p + q^2 + r^3 with p, q, and r prime. 2

%I

%S 1,3,5,7,9,11,13,21,27,33,37,45,51,61,127,351

%N Odd numbers not of the form p + q^2 + r^3 with p, q, and r prime.

%C There are no more terms < 10^11.

%t pp[n_] := Prime@ Range@ PrimePi@ n; upto[n_] := Complement[Range[1, n, 2],

%t Flatten@Table[ q^2 + r^3 + pp[n - q^2 - r^3], {r, pp[n^(1/3)]}, {q, pp@Sqrt[n - r^3]}]]; upto[10^4]

%Y Cf. A212292.

%K nonn,hard,more

%O 1,2

%A _Giovanni Resta_, Jun 09 2013

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Last modified June 18 04:41 EDT 2021. Contains 345098 sequences. (Running on oeis4.)