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A059373 Second diagonal of triangle in A059370. 1
1, -4, 8, -16, 12, -96, -480, -4672, -45520, -493120, -5798912, -73668608, -1005335552, -14671085568, -228051746304, -3762955404288, -65707303602432, -1210821292674048, -23487031074109440, -478463919131627520, -10214440549929047040, -228069193578011566080 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 171, #34.

LINKS

Table of n, a(n) for n=2..23.

FORMULA

G.f. A(x) is (R(x))^2 where R(x) is the series reversion of x*hypergeom([1,2],[],x) = sum(n>=1, n!*x^n), see Comtet. - Mark van Hoeij, Apr 20 2013

MAPLE

series(RootOf(T*hypergeom([1, 2], [], T)-x, T)^2, x=0, 21); # Mark van Hoeij, Apr 20 2013

MATHEMATICA

nmax = 23; t[n_, k_] := t[n, k] = Sum[(m+1)!*t[n-m-1, k-1], {m, 0, n-k}]; t[n_, 1] = n!; t[n_, n_] = 1; tnk = Table[t[n, k], {n, 1, nmax}, {k, 1, nmax}]; A059370 = Reverse /@ Inverse[tnk] // DeleteCases[#, 0, 2] & ; Table[A059370[[n, n - 1]], {n, 2, nmax}] (* Jean-François Alcover, Jun 14 2013 *)

PROG

(PARI)

N = 66;  x = 'x + O('x^N);

tf = sum(n=1, N, n!*x^n );

gf=serreverse(%)^2;

v = Vec(gf)

/* Joerg Arndt, Apr 20 2013 */

CROSSREFS

Cf. A059370.

Sequence in context: A011970 A111988 A110652 * A137798 A312754 A312755

Adjacent sequences:  A059370 A059371 A059372 * A059374 A059375 A059376

KEYWORD

sign,easy

AUTHOR

N. J. A. Sloane, Jan 28 2001

EXTENSIONS

Added more terms, Mark van Hoeij and Joerg Arndt, Apr 20 2013

STATUS

approved

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Last modified September 24 22:27 EDT 2018. Contains 315360 sequences. (Running on oeis4.)