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 A204519 #24 Jan 08 2018 01:47:48 %S A204519 0,0,0,1,2,4,11,20,40,109,198,396,1079,1960,3920,10681,19402,38804, %T A204519 105731,192060,384120,1046629,1901198,3802396,10360559,18819920, %U A204519 37639840,102558961,186298002 %N A204519 Square root of floor(A055851(n)/6). %C A204519 Base-6 analog of A031150 [base 10], A204512 [base 8], A204517 (base 7), A204521 [base 5], A001353 [base 3], A001542 [base 2]. For bases 4 and 9, the corresponding sequence contains all integers. %F A204519 Conjecture (for n>=8): a(n) = 10*a(n-3) - a(n-6). - _Vaclav Kotesovec_, Nov 26 2012 %F A204519 Empirical g.f.: x^4*(x^3+4*x^2+2*x+1) / (x^6-10*x^3+1). - _Colin Barker_, Sep 15 2014 %t A204519 Sqrt[Floor[Select[Range[100000],IntegerQ[Sqrt[Quotient[#^2,6]]]&]^2/6]] (* _Vaclav Kotesovec_, Nov 26 2012 *) %o A204519 (PARI) b=6;for(n=1,2e9,issquare(n^2\b) & print1(sqrtint(n^2\b),",")) %Y A204519 Cf. A055792, A055793, A055812, A204517, A204512, A204503 and A023110. %K A204519 nonn,base %O A204519 1,5 %A A204519 _M. F. Hasler_, Jan 15 2012 %E A204519 More terms from _Vaclav Kotesovec_, Nov 26 2012