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 A163631 #17 Aug 01 2017 02:53:35 %S A163631 1,10,25,46,71,98,131,166,205,250,299,350,405,462,525,590,659,734,811, %T A163631 892,977,1064,1155,1248,1343,1442,1547,1658,1773,1890,2009,2130,2253, %U A163631 2378,2507,2640,2775,2916,3059,3204,3351,3504,3659,3818,3979,4144,4313 %N A163631 Partial sums of the odd nonprimes, A014076. %C A163631 All entries besides the first are of the form 2+(k+1)^2-A007504(j), e.g., 10=2+25-17, 25=2+64-41, where the square is the sum of all odd numbers up to 1+2*k, and the 2 and A007504 represent the partial sum over the primes. %H A163631 G. C. Greubel, <a href="/A163631/b163631.txt">Table of n, a(n) for n = 1..5000</a> %F A163631 a(n) = Sum_{x= 1st odd nonprime..n-th odd nonprime}x. %t A163631 upto=200; Accumulate[Complement[Range[1,upto,2], Prime[Range[2,PrimePi[upto]]]]] (* _Harvey P. Dale_, Mar 19 2011 *) %o A163631 (PARI) lista(nn) = {my(s = 0); forstep (n=1, nn, 2, if (!isprime(n), s+= n; print1(s, ", ")););} \\ _Michel Marcus_, Aug 01 2017 %Y A163631 Cf. A014076. %K A163631 nonn %O A163631 1,2 %A A163631 _Juri-Stepan Gerasimov_, Aug 02 2009, Oct 10 2009 %E A163631 150 replaced with 250 by _R. J. Mathar_, Aug 06 2009