OFFSET
1,1
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[100], Min[DigitCount[#, 2]]>1&] (* Harvey P. Dale, Mar 09 2013 *)
PROG
(Python)
def ok(n): b = bin(n)[2:]; return b.count('0') >= 2 and b.count('1') >= 2
print(list(filter(ok, range(98)))) # Michael S. Branicky, Sep 10 2021
(Python)
def A158581(n):
def f(x):
c = n+((l:=(x+1).bit_length())*(l+1)>>1)-3
m = bin(x+1)[2:].find('0')
c += m if m>-1 else l
return c
m, k = n, f(n)
while m != k: m, k = k, f(k)
return m # Chai Wah Wu, Dec 24 2024
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Apr 16 2009
STATUS
approved