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.

A095083 Fibodious primes, i.e., primes p whose Zeckendorf-expansion A014417(p) contains an odd number of 1-fibits.

Original entry on oeis.org

2, 3, 5, 13, 17, 19, 31, 41, 43, 59, 61, 71, 73, 79, 89, 103, 107, 113, 131, 151, 167, 173, 179, 181, 191, 197, 211, 227, 229, 233, 239, 251, 257, 269, 293, 307, 313, 347, 349, 353, 367, 383, 401, 419, 431, 433, 449, 457, 463, 467, 479, 487, 491
Offset: 1

Views

Author

Antti Karttunen, Jun 01 2004

Keywords

Crossrefs

Intersection of A000040 and A020899.

Programs

  • Mathematica
    Select[Flatten[Position[Mod[DigitCount[Select[Range[0, 5000], BitAnd[#, 2 #] == 0 &], 2, 1], 2], 1]] - 1, PrimeQ] (* Amiram Eldar, Feb 07 2023 *)
  • Python
    from sympy import fibonacci, primerange
    def a(n):
        k=0
        x=0
        while n>0:
            k=0
            while fibonacci(k)<=n: k+=1
            x+=10**(k - 3)
            n-=fibonacci(k - 1)
        return x
    def ok(n): return str(a(n)).count("1")%2
    print([n for n in primerange(1, 1001) if ok(n)]) # Indranil Ghosh, Jun 08 2017