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 A077627 #13 May 17 2025 03:11:05
%S A077627 2,4,10,16,30,52,92,160,280,484,840,1456,2524,4372,7574,13120,22726,
%T A077627 39364,68182,118096,204550,354292,613654,1062880,1840964,3188644,
%U A077627 5522896,9565936,16568690,28697812,49706070,86093440,149118214,258280324,447354646,774840976,1342063940
%N A077627 Largest term in periodic part of continued fraction expansion of square root of -1+3^n.
%H A077627 Chai Wah Wu, <a href="/A077627/b077627.txt">Table of n, a(n) for n = 1..57</a>
%F A077627 a(2*m) = 2*(3^m-1); in general a(n) is close to 2*(3^(n/2)-1) and for any n, 0 <= a(n) - 2*(3^(n/2)-1) < 2. Conjecture: a(n)=ceiling(2*(3^(n/2)-1)) except for n=3, 9, 27 and all powers of 3, in this case a(n)=1+ceiling(2*(3^(n/2)-1)). - _Benoit Cloitre_, Nov 24 2002
%t A077627 Table[Max[Last[ContinuedFraction[Sqrt[ -1+3^u]]]], {u, 1, 32}]
%Y A077627 Cf. A077631, A077635.
%Y A077627 Cf. A077624, A077625, A077626.
%K A077627 nonn
%O A077627 1,1
%A A077627 _Labos Elemer_, Nov 13 2002
%E A077627 a(31)-a(37) from _Chai Wah Wu_, Oct 01 2019