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.

A124178 Numbers n such that 1 + n + n^3 + n^5 + n^7 + n^9 + n^11 + n^13 + n^15 + n^17 + n^19 is prime.

Original entry on oeis.org

1, 3, 6, 33, 36, 61, 70, 99, 168, 229, 267, 268, 321, 325, 337, 366, 387, 448, 456, 457, 498, 513, 532, 546, 591, 621, 624, 637, 835, 858, 910, 927, 961, 981, 1045, 1125, 1213, 1237, 1242, 1257, 1341, 1357, 1437, 1458, 1461, 1462, 1482, 1491, 1572, 1579, 1581
Offset: 1

Views

Author

Artur Jasinski, Dec 13 2006

Keywords

Crossrefs

Cf. A049407, similar sequences listed in A244376.

Programs

  • Magma
    [n: n in [0..2000] | IsPrime(1 +n +n^3 +n^5 +n^7 +n^9 +n^11 +n^13 +n^15 +n^17 +n^19)]; // Vincenzo Librandi, Nov 12 2010
    
  • Magma
    [n: n in [0..2000] | IsPrime(s) where s is 1+&+[n^i: i in [1..19 by 2]]]; // Vincenzo Librandi, Jun 28 2014
    
  • Mathematica
    Do[If[PrimeQ[1 + n + n^3 + n^5 + n^7 + n^9 + n^11 + n^13 + n^15 + n^17 + n^19], Print[n]], {n, 1, 1000}]
    Select[Range[3000], PrimeQ[Total[#^Range[1, 19, 2]] + 1] &] (* Vincenzo Librandi, Jun 28 2014 *)
  • PARI
    is(n)=n==1 || isprime((n^21-n)/(n^2-1)+1) \\ Charles R Greathouse IV, Jul 02 2013
    
  • Sage
    i,n = var('i,n')
    [n for n in (1..2000) if is_prime(1+(n^(2*i+1)).sum(i,0,9))] # Bruno Berselli, Jun 28 2014