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A299907 Number of decomposable lonesum n X n (0,1) matrices. 2
1, 2, 16, 344, 13528, 833432, 73871416, 8893109864, 1394602938808, 275985896665592, 67227147723919096, 19756312865302785224, 6889612105281125091448, 2811911251972519547757272, 1327454489179890318710048056, 717555570945004782603934710824 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..15.

Ken Kamano, Lonesum decomposable matrices, arXiv:1701.07157 [math.CO], 2017. Also Discrete Math., 341 (2018), 341-349.

MATHEMATICA

a[n_] := Sum[Binomial[j - 1 , k - 1 ]*j!^2*StirlingS2[n + 1, j + 1]^2/k!, {k, 0, n}, {j, k, n}]; Table[a[n], {n, 0, 15}] (* Jean-François Alcover, Feb 24 2018 *)

CROSSREFS

Main diagonal of A299906.

See also A000629, A221961 for symmetric square lonesum matrices.

See A099594 for lonesum (0,1) matrices.

Sequence in context: A009109 A268560 A275854 * A012610 A012721 A297095

Adjacent sequences:  A299904 A299905 A299906 * A299908 A299909 A299910

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 23 2018

EXTENSIONS

More terms from Jean-François Alcover, Feb 24 2018

STATUS

approved

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Last modified October 16 04:54 EDT 2021. Contains 348035 sequences. (Running on oeis4.)