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A145144 2nd column of A145142. 2
1, 3, 11, 50, 634, 6804, 71868, 789984, 11025936, 174509280, 2940903360, 51707242080, 987781034304, 20520063789120, 456583392034560, 10712403843563520, 265316096850923520, 6948996535924162560 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

LINKS

Table of n, a(n) for n=3..20.

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, 2) *(n-1)!): seq (a(n), n=3..23);

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][[3]]*(n-1)!; Table[a[n], {n, 3, 23}] (* Jean-Fran├žois Alcover, Feb 14 2014, after Maple *)

CROSSREFS

Cf. A145153.

Sequence in context: A024335 A203009 A024336 * A284702 A191341 A199212

Adjacent sequences:  A145141 A145142 A145143 * A145145 A145146 A145147

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Oct 03 2008

STATUS

approved

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Last modified April 14 05:00 EDT 2021. Contains 342941 sequences. (Running on oeis4.)