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a(n) = sqrt(2^(-n)*A004003(n)) mod 32.
1

%I #25 Sep 13 2024 08:01:59

%S 1,1,3,29,5,5,7,25,9,9,11,21,13,13,15,17,17,17,19,13,21,21,23,9,25,25,

%T 27,5,29,29,31,1,1,1,3,29,5,5,7,25,9,9,11,21,13,13,15,17,17,17,19,13,

%U 21,21,23,9,25,25,27,5,29,29,31,1,1,1,3,29,5,5,7,25,9,9,11,21,13,13,15,17

%N a(n) = sqrt(2^(-n)*A004003(n)) mod 32.

%H G. C. Greubel, <a href="/A143234/b143234.txt">Table of n, a(n) for n = 0..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/DominoTiling.html">Domino Tiling</a>

%H <a href="/index/Rec#order_32">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).

%F a(n) = A065072(n) mod 32.

%F From _G. C. Greubel_, Sep 12 2024: (Start)

%F a(n) = ( (-1)^A121262(n+1) * A109613(n) ) mod 32.

%F a(n) = a(n-32). (End)

%t (* First program *)

%t a[n_]:= Mod[If[EvenQ[n], n + 1, (-1)^((n-1)/2)*n], 32];

%t Table[a[n], {n,0,100}]

%t (* Second program *)

%t A143234[n_]:= Mod[(-1)^(Floor[Mod[n,4]/3])*(2*Floor[n/2]+1), 32];

%t Table[A143234[n], {n,0,100}] (* _G. C. Greubel_, Sep 12 2024 *)

%o (Magma)

%o A143234:= func< n | (-1)^(0^((n+1) mod 4))*(2*Floor(n/2) + 1) mod 32 >;

%o [A143234(n): n in [0..100]]; // _G. C. Greubel_, Sep 11 2024

%o (SageMath)

%o def A143234(n): return ((-1)^(0^((n+1)%4))*(2*int(n//2)+1))%32

%o [A143234(n) for n in range(101)] # _G. C. Greubel_, Sep 11 2024

%Y Cf. A004003, A065072, A109613, A121262.

%K nonn,easy

%O 0,3

%A _Eric W. Weisstein_, Jul 31 2008

%E Offset changed by Editor(s) of Oeis.