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 A180418 ( A000111(p) -(-1)^((p-1)/2) )/p, where p = prime(n). 2
 1, 3, 39, 32163, 1720635, 12345020175, 1530993953307, 44148864630732711, 797213247855503373843915, 281095572810489332134542303, 26242778669866462496740532647355475 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 COMMENTS See the formula in A000111. LINKS Table of n, a(n) for n=2..12. FORMULA a(n) = ( A000111(A000040(n)) -A070750(n) )/A000040(n). - R. J. Mathar, Sep 19 2010 MATHEMATICA t = Range[0, 60]! CoefficientList[Series[Sec@x + Tan@x, {x, 0, 60}], x]; f[n_] := (Rest[t][[Prime@n]] - (-1)^((Prime@n - 1)/2))/Prime@n; Array[f, 11, 2] (* Robert G. Wilson v, Sep 04 2010 *) CROSSREFS Cf. A000040, A000111. Sequence in context: A076628 A198411 A097421 * A166999 A319955 A317484 Adjacent sequences: A180415 A180416 A180417 * A180419 A180420 A180421 KEYWORD nonn AUTHOR Vladimir Shevelev, Sep 03 2010 EXTENSIONS Extended by R. J. Mathar, Sep 19 2010 a(8) onwards from Robert G. Wilson v, Sep 04 2010 STATUS approved

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Last modified September 23 19:57 EDT 2023. Contains 365554 sequences. (Running on oeis4.)