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A309254
Shifts left by 2 places under series reversion.
3
1, 1, 1, -1, 1, 1, -11, 41, -83, -77, 1621, -8503, 25689, -11283, -436307, 3380827, -15378675, 37938353, 87204085, -1755462619, 12722279385, -61250294425, 164643256457, 465385122833, -10366591960879, 88472237039417, -527994960273655, 2118908595206935, -1118896610239543
OFFSET
1,7
COMMENTS
Series reversion of the g.f. gives the same sequence with two initial terms (1, 1) dropped.
FORMULA
G.f. satisfies A((A(x) - x - x^2)/x^2) = x.
MATHEMATICA
Nest[InverseSeries[#] x^2 + x^2 + x &, x + O[x]^2, 14][[3]]
CROSSREFS
Sequence in context: A282321 A031389 A178495 * A360154 A217624 A097991
KEYWORD
sign
AUTHOR
STATUS
approved