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A027538
Cube of the lower triangular normalized Eulerian number matrix.
5
1, 7, 1, 163, 52, 1, 8873, 4719, 231, 1, 930581, 731646, 64966, 806, 1, 166430695, 180969681, 25235006, 610166, 2451, 1, 46667364787, 67248150516, 13560308427, 543687292, 4546137, 6840, 1, 19297882224241, 35761409868799, 9882496297869
OFFSET
1,2
FORMULA
Numerators of lower triangle of (a[ i, j ])^3 where a[ i, j ] = A(i, j)/i! if j<=i, 0 if j>i
MATHEMATICA
rows = 8; t[n_, k_] := Sum[(-1)^j*(k - j)^n*Binomial[n + 1, j], {j, 0, k}]; m = Table[If[k <= n, t[n, k]/n!, 0], {n, 1, rows}, {k, 1, rows}]; m3 = m.m.m; Table[fracs = m3[[i]]; nums = fracs // Numerator; dens = fracs // Denominator; lcm = LCM @@ dens; Table[ nums[[j]]*lcm/dens[[j]], {j, 1, i}], {i, 1, rows}] // Flatten (* Jean-François Alcover, Mar 05 2013 *)
CROSSREFS
Cf. A008292.
Sequence in context: A012034 A138324 A052122 * A334394 A027478 A009792
KEYWORD
nonn,tabl
STATUS
approved