A049184 Revert transform of 2*x*(1-x-x^3+x^4+x^6)-x/(1+x).

1, 1, 3, 11, 43, 181, 797, 3623, 16883, 80211, 387069, 1891993, 9348037, 46611111, 234246003, 1185284981, 6033612461, 30877015405, 158761428015, 819773798543, 4249143243487, 22100975481441, 115316005733921, 603418314889419

Offset

1,3

Comments

Sign diagram of generating sequence: +---++++-+-+-+-+-+-+...

Links

Table of n, a(n) for n=1..24.

Index entries for reversions of series

Maple

Order := 80:
g := 2*x*(1-x-x^3+x^4+x^6)-x/(1+x) ;
solve(series(g, x)=y, x) :
convert(%, polynom) :
seq(coeff(%, y, i), i=0..Order-1) ; # R. J. Mathar, Jul 24 2023

Prog

(PARI) a(n)=if(n<1, 0, polcoeff(serreverse(x*(1-2*x^2*(1+x-x^3-x^4-x^5)+O(x^n))/(1+x)), n))

Crossrefs

Sequence in context: A277220 A338999 A151099 * A049169 A049175 A049158

Adjacent sequences: A049181 A049182 A049183 * A049185 A049186 A049187

Keyword

nonn

Author

Olivier Gérard

Status

approved