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.

A066195 Smallest prime containing n zeros in its binary expansion.

Original entry on oeis.org

3, 2, 19, 17, 67, 131, 523, 257, 1033, 2053, 4099, 8209, 16417, 32771, 65539, 65537, 262147, 524353, 1048609, 2097169, 4194433, 8388617, 16777729, 67108913, 67239937, 134250497, 268435459, 536903681, 1073741827, 2147483713, 8589934627, 8589934609, 17179869697
Offset: 0

Views

Author

Robert G. Wilson v, Dec 15 2001

Keywords

Comments

A023416(a(n)) = n and A023416(m) <> n for m < A049084(a(m)).

Crossrefs

Cf. A061712.

Programs

  • Haskell
    import Data.List (find)
    import Data.Maybe (fromJust)
    a066195 n = fromJust $ find ((== n) . a023416) a000040_list
    -- Reinhard Zumkeller, Feb 19 2013
  • Mathematica
    Do[ k = 1; While[ Count[ IntegerDigits[ Prime[ k ], 2 ], 0 ] != n, k++ ]; Print[ Prime[ k ] ], {n, 1, 24} ]

Extensions

a(25)-a(32) from Alois P. Heinz, Jun 28 2015