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 A261935 #6 Sep 07 2015 03:31:39 %S A261935 5,23,933,2175,65849,152771,4609041,10692339,322567565,748311503, %T A261935 22575121053,52371113415,1579935906689,3665229628091,110572938347721, %U A261935 256513702853499,7738525748434325,17952293970117383,541586229452055573,1256404064205363855 %N A261935 The first of seventeen consecutive positive integers the sum of the squares of which is equal to the sum of the squares of two consecutive positive integers. %C A261935 For the first of the corresponding two consecutive positive integers, see A261933. %H A261935 Colin Barker, <a href="/A261935/b261935.txt">Table of n, a(n) for n = 1..1000</a> %H A261935 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,70,-70,-1,1). %F A261935 G.f.: x*(21*x^4+18*x^3-560*x^2-18*x-5) / ((x-1)*(x^4-70*x^2+1)). %e A261935 5 is in the sequence because 5^2 + 6^2 + ... + 21^2 = 40^2 + 41^2. %o A261935 (PARI) Vec(x*(21*x^4+18*x^3-560*x^2-18*x-5)/((x-1)*(x^4-70*x^2+1)) + O(x^40)) %Y A261935 Cf. A001652, A031138, A261932, A261933, A261934. %K A261935 nonn,easy %O A261935 1,1 %A A261935 _Colin Barker_, Sep 06 2015