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 A175033 #13 Apr 30 2016 03:39:39 %S A175033 9,15,55,89,321,519,1871,3025,10905,17631,63559,102761,370449,598935, %T A175033 2159135,3490849,12584361,20346159,73347031,118586105,427497825, %U A175033 691170471 %N A175033 Numbers n such that (ceiling(sqrt(n*n/2)))^2 - n*n/2 = 17/2. %C A175033 Let (ceiling(sqrt(n*n/2)))^2 - n*n/2 = i. Then for i=1/2 we have A002315, for i=1 we have A005319, for i=2 we have A077444, for i=7/2 we have A077446, for i=4 we have A081554. %C A175033 Conjecture: a(n) = 6*a(n-2) - a(n-4). - _Charles R Greathouse IV_, Apr 30 2016 %o A175033 (PARI) lista(nn)=for (n=1, nn, if ((ceil(sqrt(n*n/2)))^2 - n*n/2 == 17/2, print1(n, ", "));); \\ _Michel Marcus_, Jun 02 2013 %o A175033 (PARI) forstep(n=9,1e9,2, if((sqrtint(n^2\2)+1)^2==(n^2+17)/2, print1(n", "))) \\ _Charles R Greathouse IV_, Apr 30 2016 %Y A175033 Cf. A005319, A077444, A081554, A002315, A077446, %K A175033 nonn,more %O A175033 1,1 %A A175033 _Ctibor O. Zizka_, Nov 09 2009 %E A175033 More terms from _Michel Marcus_, Jun 02 2013 %E A175033 a(17)-a(22) from _Charles R Greathouse IV_, Apr 30 2016