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 A073180 #12 Jul 09 2022 11:09:23
%S A073180 1,2,2,2,2,4,2,2,2,4,2,5,2,4,4,2,2,4,2,5,4,4,2,5,2,4,2,5,2,8,2,2,4,4,
%T A073180 4,5,2,4,4,6,2,8,2,5,5,4,2,5,2,4,4,5,2,4,4,6,4,4,2,11,2,4,5,2,4,8,2,5,
%U A073180 4,8,2,5,2,4,4,5,4,8,2,6,2,4,2,11,4,4,4,6,2,10,4,5,4,4,4,5,2,4,5,5,2,8,2
%N A073180 Number of divisors of n which are not greater than the squarefree kernel of n.
%H A073180 Reinhard Zumkeller, <a href="/A073180/b073180.txt">Table of n, a(n) for n = 1..10000</a>
%F A073180 a(n) >= A034444(n).
%F A073180 a(n) = A095960(n) + 1. - _Reinhard Zumkeller_, Sep 10 2013
%e A073180 The squarefree kernel of 56 = 7*2^3 is 14 = 7*2 and the divisors <= 14 of 56 are {1, 2, 4, 7, 8, 14}, therefore a(56) = 6.
%t A073180 a[n_] := DivisorSum[n, 1 &, # <= Times @@ FactorInteger[n][[;;, 1]] &]; Array[a, 100] (* _Amiram Eldar_, Jul 09 2022 *)
%o A073180 (Haskell)
%o A073180 a073180 n = length [x | x <- a027750_row n, x <= a007947 n]
%o A073180 -- _Reinhard Zumkeller_, Sep 10 2013
%Y A073180 Cf. A000005, A007947, A034444, A073181, A073182, A095960.
%K A073180 nonn
%O A073180 1,2
%A A073180 _Reinhard Zumkeller_, Jul 19 2002