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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.

A333748 Number of nonprime divisors of n that are <= sqrt(n).

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%I A333748 #7 Apr 04 2020 10:33:05
%S A333748 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,2,1,1,1,2,1,1,1,2,1,1,1,2,1,1,
%T A333748 1,3,1,1,1,2,1,2,1,2,1,1,1,3,1,1,1,2,1,2,1,2,1,1,1,3,1,1,1,3,1,2,1,2,
%U A333748 1,1,1,4,1,1,1,2,1,2,1,3,2,1,1,3,1,1,1,3,1,3,1,2,1,1,1,4,1,1,2,3
%N A333748 Number of nonprime divisors of n that are <= sqrt(n).
%F A333748 G.f.: Sum_{k>=1} x^(A018252(k)^2) / (1 - x^A018252(k)).
%t A333748 Table[DivisorSum[n, 1 &, # <= Sqrt[n] && !PrimeQ[#] &], {n, 1, 100}]
%t A333748 nmax = 100; CoefficientList[Series[Sum[Boole[!PrimeQ[k]] x^(k^2)/(1 - x^k), {k, 1, nmax}], {x, 0, nmax}], x] // Rest
%o A333748 (PARI) a(n) = sumdiv(n, d, (d^2<=n) && !isprime(d)); \\ _Michel Marcus_, Apr 03 2020
%Y A333748 Cf. A018252, A033273, A038548, A063962, A069288, A069291, A333749, A333750, A333751.
%K A333748 nonn
%O A333748 1,16
%A A333748 _Ilya Gutkovskiy_, Apr 03 2020