A111606 - OEIS

A111606

Determinant of the upper left n X n elements excluding its first row and column of the Array T(n,m) in A109626.

2, 3, 0, 10, -48, 168, 3456, -29376, -178560, 0, 2995200, 0, -45158400, 1045094400, -14636482560, -122918584320, -370845941760, 12983695441920, -1545691830681600, -62521904633610240, 785989658251100160, -2445553599452282880

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OFFSET

1,1

COMMENTS

a(n)=0 for n's, (one less than those in A111605): 3, 10, 12, 28, 30, 33, 34, 35, 36, 37, 38, 40, 42, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 58, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 72, 73, 74, 75, 76, 77, 78, 79

LINKS

Table of n, a(n) for n=1..22.

MATHEMATICA

f[n_] := f[n] = Block[{a}, a[0] = 1; a[l_] := a[l] = Block[{k = 1, s = Sum[ a[i]*x^i, {i, 0, l - 1}]}, While[ IntegerQ[ Last[ CoefficientList[ Series[(s + k*x^l)^(1/n), {x, 0, l}], x]]] != True, k++ ]; k]; Table[a[j], {j, 0, 32}]]; g[n_, m_] := f[n][[m]]; Table[ Det[ Table[ g[i, j], {i, 2, n}, {j, 2, n}]]{n, 23}]

CROSSREFS

Cf. A109626, A111605.

Sequence in context: A012403 A012655 A012650 * A012653 A012656 A012397

Adjacent sequences: A111603 A111604 A111605 * A111607 A111608 A111609

KEYWORD

sign

AUTHOR

Paul D. Hanna and Robert G. Wilson v, Aug 01 2005

STATUS

approved