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 A298738 #8 Jun 13 2025 16:46:50 %S A298738 2,1,9,3,5,2,7,0,8,5,3,3,1,0,5,3,9,3,8,5,6,0,1,2,3,5,0,8,1,8,9,8,5,2, %T A298738 2,1,2,2,2,5,2,6,8,0,6,6,0,2,2,2,4,5,5,0,5,1,9,9,1,1,9,0,1,7,7,0,9,4, %U A298738 1,7,1,1,0,0,3,3,4,2,8,2,3,2,4,3,3,4 %N A298738 Decimal expansion of (1/2)(1 + sqrt(7 + 2*sqrt(5))). %H A298738 Clark Kimberling, <a href="/A298738/b298738.txt">Table of n, a(n) for n = 1..10000</a> %e A298738 constant = 2.1935270853310539386... = positive zero of x^2 - x - r^2, where r = golden ratio = (1+ sqrt(5))/2; see A001622. %t A298738 r = (1/2)*(1 + Sqrt[7 + 2*Sqrt[5]]) %t A298738 RealDigits[N[r, 100], 10][[1]]; (* A298738 *) %t A298738 RealDigits[(1+Sqrt[7+2*Sqrt[5]])/2,10,120][[1]] (* _Harvey P. Dale_, Jun 13 2025 *) %Y A298738 Cf. A001622, A190157, A298522, A298523, A275828. %K A298738 nonn,easy,cons %O A298738 1,1 %A A298738 _Clark Kimberling_, Feb 13 2018