This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A212292 #18 Jun 09 2013 08:35:44
%S A212292 1,3,5,7,9,17,33,43,83,179,623,713,1019
%N A212292 Odd numbers not of the form p^2 + q^2 + r with p, q, and r prime.
%C A212292 The corresponding sequence with the restriction to primes removed is empty.
%C A212292 Wang shows that all but x^{9/20+e} members of this sequence up to x are congruent to 2 mod 3, for any e > 0.
%C A212292 There are no more terms < 10^7. - _Donovan Johnson_, Jun 27 2012
%C A212292 There are no more terms < 4*10^9. - _Jud McCranie_, Jun 09 2013
%C A212292 There are no more terms < 10^11. - _Giovanni Resta_, Jun 09 2013
%D A212292 Wang Mingqiang, On sums of a prime, and a square of prime, and a k-power of prime, Northeastern Mathematical Journal 18:4 (2002), pp. 283-286.
%o A212292 (PARI) list(lim)=my(p1=vector(primepi(sqrt(lim-5.5)),i,prime(i)^2), p2=List(), v=List(), u=List([1,3,5,7,9]), t); for(i=1,#p1, for(j=i,#p1,t=p1[i]+p1[j]; if(t>lim, break, listput(p2,t)))); p2=vecsort(Vec(p2),,8); for(i=1,#p2,forprime(p=2,lim-p2[i],listput(v,p2[i]+p))); v=select(n->n%2, vecsort(Vec(v),,8)); for(i=2,#v,forstep(j=v[i-1]+2,v[i]-2,2,listput(u,j))); Vec(u)
%Y A212292 Cf. A045636, A006285, A118955, A156695, A226484.
%K A212292 nonn,hard,more
%O A212292 1,2
%A A212292 _Charles R Greathouse IV_, Jun 21 2012