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A127190 E.g.f.: sqrt((1+2*x)/(1+4*x)). 1
1, -1, 7, -75, 1089, -20025, 446535, -11715795, 353743425, -12084751665, 460905128775, -19414191656475, 895154327661825, -44844879530075625, 2425592881954016775, -140881250370301315875, 8745197742014671562625, -577792180264444615094625, 40483044280613870034474375 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

MATHEMATICA

With[{nn=20}, CoefficientList[Series[Sqrt[(1+2x)/(1+4x)], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Apr 23 2014 *)

CROSSREFS

Sequence in context: A197763 A202251 A243692 * A121316 A220215 A066302

Adjacent sequences:  A127187 A127188 A127189 * A127191 A127192 A127193

KEYWORD

sign

AUTHOR

N. J. A. Sloane, Mar 26 2007

STATUS

approved

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Last modified December 18 23:18 EST 2014. Contains 252175 sequences.