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 A178961 #19 Aug 24 2025 05:53:29
%S A178961 1,3,5,9,15,23,41,61,117,165,343,475,1049,1397,3267,4275,10419,13231,
%T A178961 33545,41965,109499,133895,359367,434123,1189795,1412351,3952757,
%U A178961 4646449,13211071,15318819,44260077,50916453,148927917,169476849
%N A178961 Partial sums of A001010.
%C A178961 Number of symmetric foldings of a strip of <= n stamps.
%H A178961 Hunter Hogan, <a href="/A178961/b178961.txt">Table of n, a(n) for n = 1..52</a>
%H A178961 <a href="/index/Fo#fold">Index entries for sequences obtained by enumerating foldings</a>
%F A178961 a(n) = Sum_{i=1..n} A001010(i).
%e A178961 a(13) = 1 + 2 + 2 + 4 + 6 + 8 + 18 + 20 + 56 + 48 + 178 + 132 + 574 = 1049 is prime.
%Y A178961 Cf. A001010.
%K A178961 nonn,changed
%O A178961 1,2
%A A178961 _Jonathan Vos Post_, Dec 31 2010