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 A000693 M0767 N0292 #21 Feb 01 2022 01:09:59 %S A000693 1,2,3,6,10,19,35,62,118,219,414,783,1497,2860,5503,10593,20471,39637, %T A000693 76918,149501,291115,567581,1108022,2165621,4237085,8297727,16264207, %U A000693 31904254,62630372,123031586,241837446,475647114,936020000,1842925873 %N A000693 Related to population of numbers of form x^2 + y^2. %D A000693 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A000693 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A000693 D. Shanks, <a href="http://dx.doi.org/10.1090/S0025-5718-1964-0159174-9">The second-order term in the asymptotic expansion of B(x)</a>, Mathematics of Computation 18 (1964), pp. 75-86. %H A000693 <a href="/index/Qua#quadpop">Index entries for sequences related to populations of quadratic forms</a> %F A000693 a(1)=1, a(2)=2, a(n) = A000074(n) + a(n-2) for n > 2. %K A000693 nonn %O A000693 1,2 %A A000693 _N. J. A. Sloane_ %E A000693 More terms from _Sean A. Irvine_, Feb 24 2011