A077533 Multiples of 3 using only prime digits (2, 3, 5 and 7).

3, 27, 33, 57, 72, 75, 222, 225, 237, 252, 255, 273, 327, 333, 357, 372, 375, 522, 525, 537, 552, 555, 573, 723, 732, 735, 753, 777, 2223, 2232, 2235, 2253, 2277, 2322, 2325, 2337, 2352, 2355, 2373, 2523, 2532, 2535, 2553, 2577, 2727, 2733, 2757, 2772, 2775

Offset: 1

Author

Amarnath Murthy, Nov 08 2002

Keywords

• base
• nonn

Links

• David A. Corneth, Table of n, a(n) for n = 1..10000
• Index entries for 10-automatic sequences.

Crossrefs

Cf. A008585 (multiples of 3), A046034 (prime digits).

Programs

Mathematica

ok3Q[n_]:=And@@(MemberQ[{2,3,5,7},#]&/@IntegerDigits[n]); Select[3Range[0,1000],ok3Q]  (* Harvey P. Dale, Mar 22 2011 *)
Select[Flatten[Table[FromDigits/@Tuples[{2,3,5,7},n],{n,4}]],Mod[#,3]==0&] (* Harvey P. Dale, Feb 27 2025 *)

Python

def pd(n): return set(str(n)) <= set("2357") # has only prime digits
def aupto(limit): return [m for m in range(0, limit+1, 3) if pd(m)]
print(aupto(3000)) # Michael S. Branicky, Mar 27 2021

Extensions

More terms from Sascha Kurz, Jan 03 2003