A326482 - OEIS

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A326482

a(n) = E2_{n}(-1) with E2_{n} the polynomials defined in A326480.

1, -4, 14, -40, 80, -64, -16, -1600, 8960, 29696, -349696, -1423360, 22384640, 89440256, -1903691776, -7615160320, 209865605120, 839460847616, -29088884064256, -116355542548480, 4951498057318400, 19805992204107776, -1015423886490075136

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OFFSET

0,2

COMMENTS

For comments see A326480.

LINKS

Table of n, a(n) for n=0..22.

MAPLE

# The function E2(n) is defined in A326480.

seq(subs(x=-1, E2(n)), n=0..22);

MATHEMATICA

T[n_, k_] := 2^n n! SeriesCoefficient[4 Exp[x z]/(Exp[z] + 1)^2, {z, 0, n}, {x, 0, k}]; Table[Sum[(-1)^k T[n, k], {k, 0, n}], {n, 0, 22}] (* Jean-François Alcover, Jul 23 2019 *)

CROSSREFS

Cf. A326480, A155585, A326481, A326482, A326483, A326484.

Sequence in context: A182819 A144141 A187594 * A331758 A291675 A066375

Adjacent sequences: A326479 A326480 A326481 * A326483 A326484 A326485

KEYWORD

sign

AUTHOR

Peter Luschny, Jul 12 2019

STATUS

approved