A294248 - OEIS

%I #12 Jun 20 2019 04:24:37

%S 0,1,1,3,1,3,2,5,4,5,4,7,4,6,4,8,6,11,6,11,7,12,7,13,8,13,10,13,10,14,

%T 10,15,10,17,12,21,13,19,12,20,12,21,13,23,17,22,16,24,17,25,17,26,18,

%U 31,18,29,19,30,19,31,19,32,23,30,22,31,22,32,22,34

%N Number of partitions of 2n into two distinct squarefree parts.

%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>

%F a(n) = Sum_{i=1..n-1} mu(i)^2 * mu(2n-i)^2, where mu is the Möbius function (A008683).

%t Table[Sum[MoebiusMu[i]^2*MoebiusMu[2 n - i]^2, {i, n - 1}], {n, 80}]

%o (PARI) A294248(n)=sum(i=1,n-1,moebius(i)^2*moebius(2*n-i)^2); \\ _R. J. Cano_, Oct 25 2017

%Y Cf. A008683, A280226.

%K nonn,easy

%O 1,4

%A _Wesley Ivan Hurt_, Oct 25 2017