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 A067546 Determinant of an n X n matrix whose diagonal are the first n nonprime numbers and all other elements are 1's. 1
 1, 3, 15, 105, 840, 7560, 83160, 1081080, 15135120, 227026800, 3859455600, 73329656400, 1466593128000, 30798455688000, 708364480824000, 17000747539776000, 425018688494400000, 11050485900854400000, 298363119323068800000, 8652530460368995200000, 268228444271438851200000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Peter Luschny, Table of n, a(n) for n = 1..100 EXAMPLE The matrix begins: 1 1 1 1 1 1 1 ... 1 4 1 1 1 1 1 ... 1 1 6 1 1 1 1 ... 1 1 1 8 1 1 1 ... 1 1 1 1 9 1 1 ... 1 1 1 1 1 10 1 ... MAPLE A067546 := proc(n) local np, f, a; with(linalg); np := proc(n) option remember; if n <= 1 then 1 else for a from np(n-1)+1 do if not isprime(a) then return(a) fi od fi end: f := (i, j) -> `if`(i=j, np(i), 1); det(matrix(n, n, f)) end: seq(A067546(i), i=1..18); # Peter Luschny, May 28 2013 MATHEMATICA NonPrime[ n_Integer ] := FixedPoint[ n + PrimePi[ # ] &, n + PrimePi[ n ] ]; Table[ Det[ DiagonalMatrix[ Table[ NonPrime[ i ] - 1, {i, 1, n} ] ] + 1 ], {n, 1, 20} ] CROSSREFS Sequence in context: A001801 A323551 A267840 * A015682 A291744 A246860 Adjacent sequences: A067543 A067544 A067545 * A067547 A067548 A067549 KEYWORD nonn AUTHOR Robert G. Wilson v, Jan 28 2002 STATUS approved

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Last modified June 5 03:05 EDT 2023. Contains 363130 sequences. (Running on oeis4.)