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A226484
Odd numbers not of the form p + q^2 + r^3 with p, q, and r prime.
2
1, 3, 5, 7, 9, 11, 13, 21, 27, 33, 37, 45, 51, 61, 127, 351
OFFSET
1,2
COMMENTS
There are no more terms < 10^11.
MATHEMATICA
pp[n_] := Prime@ Range@ PrimePi@ n; upto[n_] := Complement[Range[1, n, 2],
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]
CROSSREFS
Cf. A212292.
Sequence in context: A291343 A030155 A143448 * A261213 A130738 A239036
KEYWORD
nonn,hard,more
AUTHOR
Giovanni Resta, Jun 09 2013
STATUS
approved