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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.

A357040 Deficient composite numbers whose sum of aliquot divisors as well as product of aliquot divisors is a perfect square.

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%I A357040 #8 Sep 11 2022 19:03:46
%S A357040 75,76,124,147,153,243,332,363,477,507,524,575,688,867,892,963,1075,
%T A357040 1083,1421,1532,1573,1587,1611,1916,2032,2075,2224,2299,2401,2421,
%U A357040 2523,2572,2883,2891,3479,4107,4336,4527,4961,4975
%N A357040 Deficient composite numbers whose sum of aliquot divisors as well as product of aliquot divisors is a perfect square.
%C A357040 Deficient number in A064116; that is, the intersection of A064116 and A005100.
%C A357040 Prime numbers are excluded from this sequence as they make a trivial case: they have the sum as well as the product of aliquot divisor equal to 1.
%e A357040 Aliquot divisors of 75 are 1, 3, 5, 15, and 25. The sum is 49 = 7^2, and the product is 5625 = 75^2. Thus, 75 is in this sequence.
%t A357040 Select[Range[2, 5000], IntegerQ[Sqrt[Total[Drop[Divisors[#], -1]]]] && IntegerQ[Sqrt[Times @@ Drop[Divisors[#], -1]]] && ! PrimeQ[#] && Total[Drop[Divisors[#], -1]] < # &]
%Y A357040 Cf. A005100, A064116.
%K A357040 nonn
%O A357040 1,1
%A A357040 _Tanya Khovanova_, Sep 09 2022