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 A213360 #14 Sep 26 2015 01:17:14 %S A213360 0,6,12,18,36,42,60,78,96,126,144,174,216,222,240,258,288,342,372,450, %T A213360 492,546,624,666,732,810,828,870,912,966,1056,1122,1248,1338,1428, %U A213360 1530,1596,1674,1764,1854,1944,1998,2064,2178,2256,2382,2508,2610,2712,2850,2952,3114,3216,3330,3492,3618,3780,3894,3996,4098 %N A213360 Snowflake sequence starting with six E-toothpicks. %C A213360 The structure is the same as A161330 but without the two central E-toothpicks. All terms are multiples of 6. %H A213360 N. J. A. Sloane, <a href="/A161330/a161330.jpg">A single E-toothpick</a> %H A213360 N. J. A. Sloane, <a href="/wiki/Catalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a> %H A213360 <a href="/index/To#toothpick">Index entries for sequences related to toothpick sequences</a> %F A213360 a(n) = A161330(n+1) - 2 = 6*A161336(n). %Y A213360 Cf. A008588, A139250, A161328, A161330, A161336. %K A213360 nonn %O A213360 0,2 %A A213360 _Omar E. Pol_, Dec 16 2012