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A145141 Denominators of triangle T(n,k), n>=1, 0<=k<=n - 1, read by rows: T(n,k) is the coefficient of x^k in polynomial p_n for the n-th row sequence of A145153. 8
1, 1, 1, 1, 2, 2, 1, 3, 2, 6, 1, 4, 24, 4, 24, 1, 5, 12, 24, 12, 120, 1, 3, 360, 16, 144, 48, 720, 1, 42, 20, 45, 48, 144, 240, 5040, 1, 24, 3360, 1440, 5760, 144, 2880, 1440, 40320, 1, 180, 1260, 90720, 480, 17280, 80, 8640, 10080, 362880, 1, 20, 8400, 4032, 45360 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..60.

MAPLE

seq(seq(denom(T(n, k)), k=0..n-1), n=1..14);

MATHEMATICA

row[n_] := Module[{f, eq}, f = Function[x, Sum[a[k]*x^k, {k, 0, n-1}]]; eq = Table[f[k+1] == SeriesCoefficient[x/(1-x-x^4)/(1-x)^k, {x, 0, n}], {k, 0, n-1}]; Table[a[k], {k, 0, n-1}] /. Solve[eq] // First]; Table[row[n] // Denominator, {n, 1, 14}] // Flatten (* Jean-Fran├žois Alcover, Feb 04 2014, after Alois P. Heinz *)

CROSSREFS

See A145140 for more information on T(n, k). Diagonal gives: A000142.

Sequence in context: A030454 A262985 A296786 * A103360 A267409 A104469

Adjacent sequences:  A145138 A145139 A145140 * A145142 A145143 A145144

KEYWORD

frac,nonn,tabl

AUTHOR

Alois P. Heinz, Oct 03 2008

STATUS

approved

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Last modified April 14 22:47 EDT 2021. Contains 342971 sequences. (Running on oeis4.)