

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
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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



