OFFSET
1,2
COMMENTS
The arithmetic mean of the first k binary numbers, taken as decimal numbers, is an integer.
EXAMPLE
k = 11: (1 + 10 + 11 + 100 + 101 + 110 + 111 + 1000 + 1001 + 1010 + 1011) / 11 = 406, thus 11 is a term.
MATHEMATICA
s = 0; seq = {}; Do[s += FromDigits[IntegerDigits[k, 2]]; If[Divisible[s, k], AppendTo[seq, k]], {k, 1, 1000}]; seq (* Amiram Eldar, Feb 04 2023 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Ctibor O. Zizka, Feb 04 2023
EXTENSIONS
a(7)-a(13) from Amiram Eldar, Feb 04 2023
a(14) from Bert Dobbelaere, Feb 14 2023
STATUS
approved