A110437 - OEIS

%I #5 Mar 22 2023 14:37:28

%S 1,11,111,1101,11111,111111,1101001,11111111,111111111,1101100101,

%T 11111111111,111101111011,1101101101101,11111111111111,

%U 111111111111111,1101101101001101,11110101101110011,111111111111111111

%N A weighted sum of Jacobi function values.

%C Can be regarded as base 2 version of A110436. It would appear that a(n) has all 1's whenever 2n+1 is prime.

%F a(n) = Sum_{k=0..n} abs(Jacobi(n-k, 2k+1))*10^k.

%Y Cf. A005097, A110436.

%K easy,nonn

%O 1,2

%A _Paul Barry_, Jul 20 2005