OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..3000
MATHEMATICA
Select[Range[10000], DigitCount[#, 4, 0] == 0 && DigitCount[#, 4, 1] == 2 &] (* Vincenzo Librandi, Sep 21 2016 *)
PROG
(Python)
from sympy.ntheory import count_digits
def ok(n): c = count_digits(n, 4); return 0 not in c and c[1] == 2
print(list(filter(ok, range(439)))) # Michael S. Branicky, May 22 2021
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved