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A135212 a(n) = A078456(n)/A120271(n). 3
1, 1, 2, 4, 8, 576, 1152, 2304, 4608, 18432, 552960, 59719680, 2388787200, 100329062400, 200658124800, 802632499200, 1605264998400, 288947699712000, 6356849393664000, 444979457556480000, 10679506981355520000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
FORMULA
a(n) = A078456(n)/A120271(n).
MATHEMATICA
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}] ]
PROG
(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
CROSSREFS
Sequence in context: A302864 A061089 A067499 * A012456 A071686 A296742
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Nov 23 2007
STATUS
approved

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Last modified July 21 12:49 EDT 2024. Contains 374474 sequences. (Running on oeis4.)