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A145148 6th column of A145142. 2
1, 21, 322, 4536, 68313, 1123815, 19826015, 368232150, 7247538298, 152150838840, 3403471995560, 80589585571040, 2012376195058384, 52929114594971184, 1464737200231998960, 42545324327111272800, 1293727732305595341216 (list; graph; refs; listen; history; text; internal format)
OFFSET

7,2

LINKS

Table of n, a(n) for n=7..23.

MAPLE

row:= proc(n) option remember; local f, i, x; f:= unapply (simplify (sum ('cat (a||i) *x^i', 'i'=0..n-1) ), x); unapply (subs (solve ({seq(f(i+1)= coeftayl (x/ (1-x-x^4)/ (1-x)^i, x=0, n), i=0..n-1)}, {seq (cat (a||i), i=0..n-1)}), sum ('cat (a||i) *x^i', 'i'=0..n-1) ), x); end: a:= n-> `if` (n=0, 0, coeftayl (row(n)(x), x=0, 6) *(n-1)!): seq (a(n), n=7..26);

MATHEMATICA

row[n_] := row[n] = Module[{f, a, 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}]; List @@ f[1] /. Solve[eq] // First]; a[n_] := row[n][[7]]*(n-1)!; Table[a[n], {n, 7, 26}] (* Jean-Fran├žois Alcover, Feb 14 2014, after Maple *)

CROSSREFS

Cf. A145153.

Sequence in context: A141267 A016262 A001233 * A214099 A340097 A237856

Adjacent sequences:  A145145 A145146 A145147 * A145149 A145150 A145151

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Oct 03 2008

STATUS

approved

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Last modified April 14 05:21 EDT 2021. Contains 342943 sequences. (Running on oeis4.)