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

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.

Links

Table of n, a(n) for n=1..16.

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

Adjacent sequences: A226481 A226482 A226483 * A226485 A226486 A226487

Keyword

nonn,hard,more

Author

Giovanni Resta, Jun 09 2013

Status

approved