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A108580
Numbers whose sum of bits when written in binary > sum of decimal digits.
2
10, 11, 30, 31, 100, 101, 102, 103, 110, 111, 120, 121, 200, 201, 210, 211, 220, 221, 300, 301, 310, 311, 500, 501, 510, 511, 1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007, 1010, 1011, 1012, 1013, 1014, 1015, 1020, 1021, 1022, 1023, 1100, 1101, 1102, 1103
OFFSET
1,1
COMMENTS
The sequence is infinite because 10^n, n = 1,2,3, .... are terms. - Marius A. Burtea, Sep 07 2019
LINKS
EXAMPLE
1103 is on the list since 1103 is 10001001111 (sum=6), 1+1+0+3=5.
MATHEMATICA
Select[Range[1103], Total@IntegerDigits[#, 2] > Total@IntegerDigits[#, 10] &] (* Amiram Eldar, Sep 07 2019 *)
PROG
(PARI) isok(n) = hammingweight(n) > sumdigits(n); \\ Michel Marcus, Sep 07 2019
(Magma) [n:n in [1..1200]| &+Intseq(n, 2) gt &+Intseq(n, 10)]; // Marius A. Burtea, Sep 07 2019
(Python)
def ok(n): return sum(map(int, str(n))) < bin(n).count('1')
print(list(filter(ok, range(1104)))) # Michael S. Branicky, Oct 11 2021
CROSSREFS
Subsequence of A325483.
Sequence in context: A086458 A179856 A098795 * A356279 A041208 A041485
KEYWORD
nonn,base
AUTHOR
John L. Drost, Jul 25 2005
EXTENSIONS
a(36) added by Marius A. Burtea, Sep 07 2019
STATUS
approved