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 A303283 #6 Apr 21 2018 20:58:27
%S A303283 42,78,105,114,130,174,182,195,210,222,230,231,258,266,285,318,345,
%T A303283 357,366,370,390,406,426,429,435,455,462,470,474,483,494,518,534,546,
%U A303283 555,570,598,602,606,610,627,638,642,645,651,663,665,678,690,705,714,715
%N A303283 Squarefree numbers whose prime indices have no common divisor other than 1 but are not pairwise coprime.
%C A303283 A prime index of n is a number m such that prime(m) divides n. Two or more numbers are coprime if no pair of them has a common divisor other than 1.
%C A303283 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
%e A303283 The sequence of strict integer partitions whose Heinz numbers belong to this sequence begins (4,2,1), (6,2,1), (4,3,2), (8,2,1), (6,3,1), (10,2,1), (6,4,1), (6,3,2), (4,3,2,1), (12,2,1), (9,3,1), (5,4,2), (14,2,1), (8,4,1), (8,3,2), (16,2,1), (9,3,2), (7,4,2), (18,2,1), (12,3,1), (6,3,2,1).
%t A303283 primeMS[n_]:=If[n===1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A303283 Select[Range[400],SquareFreeQ[#]&&!CoprimeQ@@primeMS[#]&&GCD@@primeMS[#]===1&]
%Y A303283 Cf. A000837, A001222, A018783, A051424, A056239, A078374, A168532, A289508, A289509, A296150, A298748, A300486, A302569, A302696, A302796, A303138, A303139, A303140, A303282.
%K A303283 nonn
%O A303283 1,1
%A A303283 _Gus Wiseman_, Apr 20 2018