A067560 - OEIS

A067560

Determinant of n X n matrix whose rows are cyclic permutations of 1..n-th nonprime (A018252).

1, -15, -209, 3895, 58828, -987012, -32251150, 1259339776, 33525669556, -973603483875, -54655725143297, 3308661532816640, 125757090803564374, -5201646874854669888, -415867280417850247000, 19065322853430198710625, 898206693379667144028053

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OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..300

EXAMPLE

a(4) = 3895 because this is the determinant of [(1,4,6,8), (4,6,8,1), (6,8,1,4), (8,1,4,6)]

MATHEMATICA

NonPrime[n_Integer] := FixedPoint[n + PrimePi[ # ] &, n + PrimePi[n]]; f[n_] := Module[{a = Table[ NonPrime[i], {i, 1, n} ], m = {}, k = 0}, While[k < n, m = Append[m, RotateLeft[a, k]]; k++ ]; Det[m]]; Table[ f[n], {n, 1, 18} ]

Module[{nn=30, np, len}, np=Select[Range[nn], !PrimeQ[#]&]; len=Length[ np]; Table[ Det[NestList[RotateLeft[#]&, Take[np, n], n-1]], {n, len}]] (* Harvey P. Dale, May 30 2021 *)

CROSSREFS

Sequence in context: A274563 A122572 A028230 * A019553 A234249 A112496

Adjacent sequences: A067557 A067558 A067559 * A067561 A067562 A067563

KEYWORD

easy,sign

AUTHOR

Robert G. Wilson v, Jan 29 2002

STATUS

approved