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A203773 Vandermonde sequence using x^2 + y^2 applied to (0,1,1,2,2,...,floor(n/2)). 5

%I #8 Jan 14 2013 10:20:15

%S 1,1,2,200,160000,24336000000,66627100800000000,

%T 77020928524800000000000000,2849158187989401600000000000000000000,

%U 78690953969671659336819671040000000000000000000000

%N Vandermonde sequence using x^2 + y^2 applied to (0,1,1,2,2,...,floor(n/2)).

%C See A093883 for a discussion and guide to related sequences.

%t f[j_] := Floor[j/2]; z = 20;

%t u := Product[f[j]^2 + f[k]^2, {j, 1, k - 1}]

%t v[n_] := Product[u, {k, 2, n}]

%t Table[v[n], {n, 1, z}] (* A203773 *)

%t Table[v[n + 1]/v[n], {n, 1, z}]

%t Table[Sqrt[v[n + 1]/v[n]], {n, 1, z}]

%t Table[Sqrt[v[2 n]/v[2 n - 1]], {n, 1, z}] (* A203774 *)

%t Table[Sqrt[v[2 n + 1]/(2 v[2 n])],

%t {n, 1, z}] (* A203775 *)

%t %/%% (* A000027 *)

%K nonn

%O 1,3

%A _Clark Kimberling_, Jan 05 2012

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Last modified September 1 06:23 EDT 2024. Contains 375575 sequences. (Running on oeis4.)