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 A256247 #12 Mar 25 2015 19:00:56 %S A256247 2,5,7,23,33,51,65,97,99,111,115,133,137,141,143,161,171,175,177,199, %T A256247 207,237,241,253,271,273,275,287,309,313,315,337,387,417,423,429,435, %U A256247 481,507,513,541,543,557,561,589,591,613,625,631,639,651,661,677,679,727,745,769,773,777,789 %N A256247 a(n) = sqrt(2*A256246(n) + prime(A256246(n))). %C A256247 Except for the first term, 2, all terms are odd. %H A256247 Zak Seidov, <a href="/A256247/b256247.txt">Table of n, a(n) for n = 1..252</a> %e A256247 a(1) = 2 = sqrt(2*A256246(1) + prime(A256246(1))) = sqrt(2*1 + prime(1)) = sqrt(2*1+2) = sqrt(4), %e A256247 a(2) = 5 = sqrt(2*6 + prime(6)) = sqrt(2*6+13) = sqrt(25). %Y A256247 Cf. A000040 (primes), A256246. %K A256247 nonn %O A256247 1,1 %A A256247 _Zak Seidov_, Mar 20 2015