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 A339748 #9 Dec 12 2022 01:41:29
%S A339748 1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,
%T A339748 1,43,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,
%U A339748 1,1,1,43,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1,1,7,1,1,1,1
%N A339748 a(n) = (6^(valuation(n, 6) + 1) - 1) / 5.
%C A339748 Sum of powers of 6 dividing n.
%H A339748 Amiram Eldar, <a href="/A339748/b339748.txt">Table of n, a(n) for n = 1..10000</a>
%F A339748 G.f.: Sum_{k>=0} 6^k * x^(6^k) / (1 - x^(6^k)).
%F A339748 L.g.f.: -log(Product_{k>=0} (1 - x^(6^k))).
%F A339748 Dirichlet g.f.: zeta(s) / (1 - 6^(1 - s)).
%t A339748 Table[(6^(IntegerExponent[n, 6] + 1) - 1)/5, {n, 1, 100}]
%t A339748 nmax = 100; CoefficientList[Series[Sum[6^k x^(6^k)/(1 - x^(6^k)), {k, 0, Floor[Log[6, nmax]] + 1}], {x, 0, nmax}], x] // Rest
%Y A339748 Cf. A038712, A080278, A088842, A122841, A234959, A323921, A339747.
%K A339748 nonn
%O A339748 1,6
%A A339748 _Ilya Gutkovskiy_, Dec 15 2020