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 A067066 #7 May 22 2016 19:02:00
%S A067066 1,2,1,3,4,1,4,9,6,1,5,16,21,8,1,6,25,52,45,10,1,7,36,105,160,93,12,1,
%T A067066 8,49,186,425,484,189,14,1,9,64,301,936,1705,1456,381,16,1,10,81,456,
%U A067066 1813,4686,6825,4372,765,18,1,11,100,657,3200,10885,23436,27305,13120,1533,20,1
%N A067066 Number of Gnutella users reachable with given connections and hops.
%H A067066 Jordan Ritter, <a href="http://www.darkridge.com/~jpr5/doc/gnutella.html">Why Gnutella Can't Scale. No, Really.</a>
%F A067066 T(n,k) = n * Sum_{i=0..k-1} (n-1)^i.
%e A067066 1 1 1 1 1 1 1 ...
%e A067066 2 4 6 8 10 12 14 ...
%e A067066 3 9 21 45 93 189 381 ...
%e A067066 4 16 52 160 484 1456 4372 ...
%e A067066 5 25 105 425 1705 6825 27305 ...
%e A067066 6 36 186 936 4686 23436 117186 ...
%e A067066 7 49 301 1813 10885 65317 391909 ...
%Y A067066 Cf. A104881.
%K A067066 nonn,tabl,easy
%O A067066 1,2
%A A067066 _Michael Somos_, Feb 17 2002
%E A067066 Offset corrected, _R. J. Mathar_, May 22 2016