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a(n) = Sum_{k=0..4n} (A035343(n,k) mod 2) * 2^k.
1

%I #21 Jun 17 2016 09:04:45

%S 1,31,341,6483,69905,2027247,21041413,417263459,4311810305,

%T 133666119455,1461703693397,27806864656979,299071474565137,

%U 8708265758097903,90161415181374469,1785159701350222947,18447025552981295105

%N a(n) = Sum_{k=0..4n} (A035343(n,k) mod 2) * 2^k.

%C a(n) is a binary palindrome (A006995) of 4n+1 bits since A035343(n,k) = A035343(n,4n-k), k=0..4n and A035343(n,0) = A035343(n,4n) = 1.

%H Gheorghe Coserea, <a href="/A274180/b274180.txt">Table of n, a(n) for n = 0..200</a>

%o (PARI)

%o a(n) = subst(lift(Pol(Mod([1, 1, 1, 1, 1], 2), 'x)^n), 'x, 2);

%o vector(17,n,a(n-1))

%Y Cf. A035343.

%K nonn,base

%O 0,2

%A _Gheorghe Coserea_, Jun 12 2016