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A264028 Triangle read by rows: T(n, k) = Sum_{t=k..n-3} (-1)^(t-k)*(n-t)!*binomial(t,k)*binomial(n-3,t). 0
6, 18, 6, 78, 36, 6, 426, 234, 54, 6, 2790, 1704, 468, 72, 6, 21234, 13950, 4260, 780, 90, 6, 183822, 127404, 41850, 8520, 1170, 108, 6, 1781802, 1286754, 445914, 97650, 14910, 1638, 126, 6, 19104774, 14254416, 5147016, 1189104, 195300, 23856, 2184, 144, 6 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

3,1

LINKS

Table of n, a(n) for n=3..47.

J. Liese, J. Remmel, Q-analogues of the number of permutations with k-excedances, PU. M. A. Vol. 21 (2010), No. 2, pp. 285-320 (see E_{n,3}(x) in Table 1 p. 291).

EXAMPLE

Triangle begins:

6;

18, 6;

78, 36, 6;

426, 234, 54, 6;

2790, 1704, 468, 72, 6;

MATHEMATICA

Table[Sum[(-1)^(t - k) (n - t)!*Binomial[t, k] Binomial[n - 3, t], {t, k, n - 3}], {n, 3, 11}, {k, 0, n - 3}] // Flatten (* Michael De Vlieger, Nov 01 2015 *)

PROG

(PARI) tabl(nn) = {for (n=3, nn, for (k=0, n-2, print1(sum(t=k, n-2, (-1)^(t-k)*(n-t)!*binomial(t, k)*binomial(n-2, t)), ", "); ); print(); ); }

CROSSREFS

Cf. A008290, A123513.

Sequence in context: A077022 A074923 A093061 * A078741 A248461 A129870

Adjacent sequences:  A264025 A264026 A264027 * A264029 A264030 A264031

KEYWORD

nonn,tabl

AUTHOR

Michel Marcus, Nov 01 2015

STATUS

approved

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Last modified July 28 19:33 EDT 2021. Contains 346335 sequences. (Running on oeis4.)