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 A294493 #8 Nov 02 2017 15:53:07
%S A294493 1,2,10,20,100,110,210,1010,1110,11110,21110,101110,201110,1001110,
%T A294493 1101110,2101110,10101110,11101110,111101110,211101110,1011101110,
%U A294493 2011101110,10011101110,11011101110,21011101110,101011101110,111011101110,10111011101110,20111011101110
%N A294493 a(n) = Sum_{m=0..n} 3^v3(m!), where v3(m!) is the exponent of the highest power of 3 dividing n!, expressed in base 3.
%C A294493 Partial sums of A060828 expressed in ternary.
%H A294493 SÃlvia Casacuberta, <a href="https://arxiv.org/abs/1710.11484">Irrationality of the sum of a p-adic series</a>, arXiv:1710.11484 [math.NT], 2017.
%t A294493 FromDigits@ IntegerDigits[#, 3] & /@ Accumulate@ Array[3^IntegerExponent[#!, 3] &, 29, 0] (* _Michael De Vlieger_, Nov 01 2017 *)
%o A294493 (PARI) a(n) = fromdigits(digits(sum(m=0, n, 3^valuation(m!, 3)), 3), 10);
%Y A294493 Cf. A060828.
%K A294493 nonn,base
%O A294493 0,2
%A A294493 _Michel Marcus_, Nov 01 2017