cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A259644 Numerators of sum(1/A112373(k): k=0..n), denominators = A112373.

Original entry on oeis.org

1, 2, 5, 31, 2419, 176795035, 883922739668546300971, 1511516294872733607299090320742127160367108420362968907
Offset: 0

Views

Author

Reinhard Zumkeller, Jul 02 2015

Keywords

Examples

			Sum(1/A112373(k)) = 1, 2, 5/2, 31/12, 2419/936, 176795035/68408496, ...
		

Crossrefs

Cf. A112373.

Programs

  • Haskell
    import Data.Ratio (numerator)
    a259644 n = a259644_list !! n
    a259644_list = map numerator $
                   scanl1 (+) $ map (recip . fromIntegral) a112373_list
  • Mathematica
    (* b = A112373 *)
    b[n_] := b[n] = If[n < 2, 1, (b[n-1]^3 + b[n-1]^2)/b[n-2]];
    a[n_] := Sum[1/b[k], {k, 0, n}] // Numerator;
    Table[a[n], {n, 0, 7}] (* Jean-François Alcover, Dec 15 2018 *)