|
|
A039279
|
|
Numbers whose base-4 representation has the same nonzero number of 0's and 3's.
|
|
1
|
|
|
12, 19, 28, 35, 44, 49, 50, 52, 56, 71, 75, 77, 78, 83, 92, 99, 108, 113, 114, 116, 120, 135, 139, 141, 142, 147, 156, 163, 172, 177, 178, 180, 184, 195, 197, 198, 201, 202, 204, 209, 210, 212, 216, 225, 226, 228, 232, 240, 271, 279, 283, 285, 286, 295, 299
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
MATHEMATICA
|
Select[Range[300], DigitCount[#, 4, 0]==DigitCount[#, 4, 3]>0&] (* Harvey P. Dale, Oct 30 2021 *)
|
|
PROG
|
(Python)
from sympy.ntheory import count_digits
def ok(n): c = count_digits(n, 4); return c[0] == c[3] > 0
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,base,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|