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A202408
Denominator of series coefficients for Archimedes' spiral which transforms into Galileo's spiral.
1
1, 2, 32, 768, 49152, 1, 56623104, 3170893824, 541165879296, 175337744891904, 28054039182704640, 29389945810452480, 2844006276185865584640, 147888326361665010401280, 25765432859454526256578560, 83480002464632665071314534400
OFFSET
0,2
COMMENTS
Numerators are listed in A202407 which is the main entry for these sequences.
MATHEMATICA
km = 16; a[0] = 0; r[t_] = Sum[a[k] t^(2 k), {k, 0, km}]; coes = CoefficientList[Series[r'[t]^2 + r[t]^2 - t^2 , {t, 0, 2 km}], t] // Union // Rest; Table[a[k], {k, 0, km}] /. Solve[Thread[coes == 0] ] // Last // Most // Denominator (* Jean-François Alcover, Jan 18 2013 *)
CROSSREFS
Sequence in context: A198599 A009517 A354382 * A069182 A333772 A012233
KEYWORD
nonn,frac
AUTHOR
Mikhail Gaichenkov, Dec 19 2011
EXTENSIONS
Corrected and extended by Max Alekseyev, Dec 19 2011
STATUS
approved