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A135212 a(n) = A078456(n)/A120271(n). 3

%I #10 Oct 02 2016 07:38:39

%S 1,1,2,4,8,576,1152,2304,4608,18432,552960,59719680,2388787200,

%T 100329062400,200658124800,802632499200,1605264998400,288947699712000,

%U 6356849393664000,444979457556480000,10679506981355520000

%N a(n) = A078456(n)/A120271(n).

%H G. C. Greubel, <a href="/A135212/b135212.txt">Table of n, a(n) for n = 1..250</a>

%F a(n) = A078456(n)/A120271(n).

%t Table[ Det[ DiagonalMatrix[ Table[ Prime[i+1]-1, {i, 1, n-1} ] ] + 1 ], {n, 1, 50} ] / Numerator[ Table[ Sum[ 1/(Prime[i]-1), {i, 1, n} ], {n, 1, 50}] ]

%o (PARI) a(n) = matdet(matrix(n-1, n-1, j, k, if (j==k, prime(j+1), 1)))/numerator(sum(k=1, n, 1/(prime(k)-1))); \\ _Michel Marcus_, Oct 02 2016

%Y Cf. A078456, A120271.

%K nonn

%O 1,3

%A _Alexander Adamchuk_, Nov 23 2007

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Last modified April 23 05:37 EDT 2024. Contains 371906 sequences. (Running on oeis4.)