A216873 Numbers n such that 2^n in decimal has at least 9 of the digits 0-9 appearing a prime number of times.

88, 104, 113, 114, 120, 141

Offset

1,1

Comments

This is a subsequence of A216872, which has 8 in place of 9. See that sequence for more comments and a PARI/GP program.

No other terms below 5*10^6. - James G. Merickel, Dec 29 2015

Links

Table of n, a(n) for n=1..6.

Prog

(Python)
from sympy import isprime
A216873_list, n = [], 1
for i in range(2*10**6):
    s = str(n)
    if sum(isprime(s.count(d)) for d in '0123456789') >= 9:
        A216873_list.append(i)
    n *= 2 # Chai Wah Wu, Nov 12 2015

Crossrefs

Cf. A216872.

Sequence in context: A356368 A068356 A215830 * A114166 A350324 A183186

Adjacent sequences: A216870 A216871 A216872 * A216874 A216875 A216876

Keyword

nonn,base,hard,more

Author

James G. Merickel, Sep 18 2012

Status

approved