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 A294098 #19 Jul 27 2021 11:04:47 %S A294098 0,0,1,0,3,1,4,1,4,2,5,2,7,4,9,4,8,1,11,4,12,4,14,5,15,5,13,8,14,8,17, %T A294098 9,19,7,18,3,19,8,23,10,25,9,26,9,22,12,25,12,27,11,27,12,28,5,31,12, %U A294098 32,12,34,13,36,12,31,18,34,18,37,19,39,17,40,7,41 %N A294098 Number of partitions of 2n into two parts such that one part is squarefree and the other part is nonsquarefree. %H A294098 <a href="/index/Par#part">Index entries for sequences related to partitions</a> %F A294098 a(n) = n - Sum_{i=1..n} [c(i) = c(2*n-i)], where [] is the Iverson bracket and c is the squarefree characteristic (A008966). %F A294098 a(n) = Sum_{i=1..n} mu(i)^2 * (1-mu(2*n-i)^2) + (1-mu(i)^2) * mu(2*n-i)^2, where mu is the Möbius function (A008683). - _Wesley Ivan Hurt_, Nov 18 2017 %t A294098 Table[n - Sum[KroneckerDelta[MoebiusMu[k]^2, MoebiusMu[2 n - k]^2], {k, n}], {n, 80}] %t A294098 Table[Count[IntegerPartitions[2n,{2}],_?(Total[Boole[ SquareFreeQ/@#]] == 1&)],{n,80}] (* _Harvey P. Dale_, Jul 27 2021 *) %Y A294098 Cf. A008683, A008966, A294097. %K A294098 nonn,easy %O A294098 1,5 %A A294098 _Wesley Ivan Hurt_, Oct 22 2017