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 A259986 #13 Jul 18 2015 14:49:49 %S A259986 3,9,81,81,6561,29889,76545,636417,3995649,24151041,326481921, %T A259986 689278977,11573190657,76876660737,155240824833,2035980763137, %U A259986 4857090670593,55637069004801,157197025673217,1375916505694209,19656708706009089,129341461907898369 %N A259986 This sequence and A259987 are base-6 analogs of A007185 and A016090, written in base 10. %C A259986 See Schut (1991) for precise definition. %C A259986 Ignoring repetitions, the subsequence of A237583 of terms ending in 3 in base 6. - _Eric M. Schmidt_, Jul 18 2015 %D A259986 C. P. Schut, Idempotents. Report AM-R9101, Centrum voor Wiskunde en Informatica, Amsterdam, 1991. %H A259986 Eric M. Schmidt, <a href="/A259986/b259986.txt">Table of n, a(n) for n = 1..1000</a> %o A259986 (Sage) def a(n) : return crt(1, 0, 2^n, 3^n) # _Eric M. Schmidt_, Jul 18 2015 %Y A259986 Cf. A007185, A016090, A201821, A237583, A259986-A259991. %K A259986 nonn,base %O A259986 1,1 %A A259986 _N. J. A. Sloane_, Jul 13 2015 %E A259986 More terms from _Eric M. Schmidt_, Jul 18 2015