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a(n) = Sum_{k=0..n} A105595(k)*(-1)^k*A105595(n-k) (interpolated zeros suppressed).
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%I #12 Aug 01 2023 07:37:59

%S 1,5,13,17,25,25,33,21,9,-15,-23,-3,-11,-31,-47,-35,5,-47,-83,-75,

%T -211,-295,-267,-267,-99,-107,-159,-415,-347,-679,-279,-583,-395,-839,

%U -1031,-1291,-1139,-1883,-1519,-1643,-855,-1591,-1571,-1851,-1195,-2419,-1923,-2179,-891,-1919,-2535

%N a(n) = Sum_{k=0..n} A105595(k)*(-1)^k*A105595(n-k) (interpolated zeros suppressed).

%C Conjecture : a(2n)=1 mod 4 for all n, a(2n+1)=0 for all n.

%p A105596 := proc(n)

%p add(A105595(k)*(-1)^k*A105595(2*n-k),k=0..2*n) ;

%p end proc:

%p seq(A105596(n),n=0..50) ; # _R. J. Mathar_, Nov 28 2014

%t A105594[n_, k_] := A105594[n, k] = Sum[Abs[MoebiusMu[ Binomial[n, j]]*Mod[Binomial[j, k], 2]], {j, 0, n}]//Mod[#, 2]&;

%t A105595[n_] := Sum[A105594[n, k], {k, 0, n}];

%t a[n_] := Sum[A105595[k]*(-1)^k*A105595[2n - k], {k, 0, 2n}];

%t Table[a[n], {n, 0, 50}] (* _Jean-François Alcover_, Aug 01 2023, after _R. J. Mathar_ *)

%Y Cf. A105594, A105595.

%K easy,sign

%O 0,2

%A _Paul Barry_, Apr 14 2005