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 A083901 #8 Jan 04 2024 01:49:06
%S A083901 1,2,2,3,2,4,1,3,2,4,2,6,2,3,4,4,1,4,1,6,3,4,2,7,3,4,2,4,1,8,2,5,4,3,
%T A083901 3,7,1,2,3,7,2,7,2,6,5,4,1,8,1,6,3,6,2,5,4,5,2,2,1,12,2,4,4,6,4,8,1,4,
%U A083901 3,6,1,8,1,2,5,3,2,6,1,8,2,3,1,9,2,3,2,6,1,9,2,5,3,2,2,9,1,3,4,9,2,7,2,7,7
%N A083901 Number of divisors of n with largest digit <= 6 (base 10).
%F A083901 a(n) = A083900(n) + A083893(n) = A083902(n) - A083894(n).
%F A083901 Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = Sum_{k>=1} 1/A007093(k) = 7.32338572355014919630... . - _Amiram Eldar_, Jan 04 2024
%t A083901 a[n_] := DivisorSum[n, 1 &, Max[IntegerDigits[#]] <= 6 &]; Array[a, 100] (* _Amiram Eldar_, Jan 04 2024 *)
%Y A083901 Cf. A054055, A000005, A007093, A083893, A083894, A083900, A083902.
%K A083901 nonn,base
%O A083901 1,2
%A A083901 _Reinhard Zumkeller_, May 08 2003