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 A307784 #13 Apr 29 2019 17:22:54 %S A307784 1,2,3,4,5,6,5,3,4,5,4,3,4,5,6,7,8,9,8,7,8,9,10,8,5,6,7,8,9,10,9,7,8, %T A307784 9,8,7,8,9,10,8,5,6,7,8,9,10,9,8,9,10,11,12,13,14,13,12,11,9,10,11,12, %U A307784 13,12,11,12,13,14,15,14,12,13,14,13,12,11,12,14 %N A307784 a(n) is the square root of A034175(n) + A034175(n+1). %C A307784 The sum of two consecutive terms of A034175 is always a perfect square. %H A307784 Rémy Sigrist, <a href="/A307784/b307784.txt">Table of n, a(n) for n = 0..10000</a> %F A307784 a(n)^2 = A034175(n) + A034175(n+1). %e A307784 For n = 12: %e A307784 - A034175(12) + A034175(13) = 7 + 9 = 16 = 4^2, %e A307784 - hence a(12) = 4. %o A307784 (PARI) p=0; s=0; for (n=1, 77, s+=2^p; for (v=0, oo, if (!bittest(s,v) && issquare(p+v), print1 (sqrtint(p+v) ", "); p=v; break))) %Y A307784 Cf. A034175. %K A307784 nonn %O A307784 0,2 %A A307784 _Rémy Sigrist_, Apr 28 2019