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.

A147813 Primes prime(n) such that (-prime(n) + 2*prime(n+1) - prime(n+2))/((1 - prime(n) + prime(n+1))^(3/2)) < 0.

Original entry on oeis.org

2, 3, 5, 11, 17, 19, 29, 41, 43, 47, 59, 71, 79, 83, 101, 107, 109, 127, 137, 149, 151, 163, 167, 179, 191, 197, 199, 227, 229, 239, 251, 257, 269, 281, 283, 311, 313, 331, 347, 349, 353, 367, 379, 383, 397, 401, 419, 431, 439, 443, 461, 463, 487, 499, 503, 521
Offset: 1

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Author

Roger L. Bagula, Nov 13 2008

Keywords

Crossrefs

Cf. A036263, A147812 (complement with respect to A000040).

Programs

  • Haskell
    import Data.List (findIndices)
    a147813 n = a147813_list !! (n-1)
    a147813_list = map (a000040 . (+ 1)) $ findIndices (>= 0) a036263_list
    -- Reinhard Zumkeller, Jan 20 2012
  • Mathematica
    d2[n_] = Prime[n + 2] - 2*Prime[n + 1] + Prime[n]; d1[n_] = Prime[n + 1] - Prime[n]; k[n_] = -d2[n]/(1 + d1[n])^(3/2); Flatten[Table[If[k[n]<= 0, Prime[n], {}], {n, 1, 100}]]

Formula

Primes prime(n) such that (-prime(n) + 2*prime(n+1) - prime(n+2))/((1 - prime(n) + prime(n+1))^(3/2)) < 0.

Extensions

Edited by Alonso del Arte and Joerg Arndt, Nov 01 2013