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A145145 3rd column of A145142. 2
1, 6, 35, 225, 2464, 29932, 375164, 4877100, 73016856, 1229669496, 22393143552, 430226343456, 8838633396384, 195021406776960, 4592633620285440, 114230969866103040, 2991995263667137536, 82505359191832358400 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

LINKS

Table of n, a(n) for n=4..21.

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, 3) *(n-1)!): seq (a(n), n=4..25);

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][[4]]*(n-1)!; Table[a[n], {n, 4, 25}] (* Jean-François Alcover, Feb 14 2014, after Maple *)

CROSSREFS

Cf. A145153.

Sequence in context: A213452 A000399 A081051 * A289383 A249476 A244267

Adjacent sequences:  A145142 A145143 A145144 * A145146 A145147 A145148

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Oct 03 2008

STATUS

approved

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Last modified April 14 12:04 EDT 2021. Contains 342949 sequences. (Running on oeis4.)