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.

A225222 Primes with more than twice as many 1's as 0's in binary.

Original entry on oeis.org

3, 7, 11, 13, 23, 29, 31, 47, 59, 61, 79, 103, 107, 109, 127, 191, 223, 239, 251, 367, 379, 383, 431, 439, 443, 463, 479, 487, 491, 499, 503, 509, 607, 631, 701, 719, 727, 733, 743, 751, 757, 761, 823, 827, 829, 859, 863, 877, 883, 887, 911, 919, 941, 947, 953, 967, 971
Offset: 1

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Naslund proves that this sequence (and related ones) is infinite and gives an asymptotic upper bound.

Crossrefs

Programs

  • Mathematica
    okQ[n_] := Module[{b = IntegerDigits[n, 2]}, Count[b, 1] > 2*Count[b, 0]]; Select[Prime[Range[200]], okQ] (* T. D. Noe, May 02 2013 *)
  • PARI
    has(n)=3*hammingweight(n)>2*#binary(n)
    select(has,primes(500))