A278077 Series reversion of x + x^2 - x^5 - x^6 - x^7.

0, 1, -1, 2, -5, 15, -48, 161, -558, 1985, -7205, 26577, -99333, 375366, -1431740, 5504906, -21313444, 83023692, -325152548, 1279534265, -5056843296, 20062512404, -79875018700, 319021150220, -1277884425750, 5132427441726, -20664323290494, 83388318193363

Offset

0,4

Links

Robert Israel, Table of n, a(n) for n = 0..1593

Formula

G.f. g(x) satisfies g(x) + g(x)^2 - g(x)^5 - g(x)^6 - g(x)^7 = x with g(0)=0. - Robert Israel, Feb 08 2017

Maple

S:= series(RootOf(x+x^2-x^5-x^6-x^7=y, x), y, 51):
seq(coeff(S, y, j), j=0..50); # Robert Israel, Feb 08 2017

Mathematica

CoefficientList[InverseSeries[t+t^2-t^5-t^6-t^7 + O[t]^28,  t], t]

Prog

(Sage)
R.<t> = PowerSeriesRing(ZZ)
q = (t+t^2-t^5-t^6-t^7).O(28)
print(q.reverse().list())
(PARI) concat(0, Vec(serreverse(x + x^2 - x^5 - x^6 - x^7 + O(x^30)))) \\ Michel Marcus, Jan 01 2017

Crossrefs

Sequence in context: A366041 A218251 A203067 * A145072 A149927 A035350

Adjacent sequences: A278074 A278075 A278076 * A278078 A278079 A278080

Keyword

sign

Author

Peter Luschny, Jan 01 2017

Status

approved