%I
%S 2,5,22,25,52,55,222,225,252,255,522,525,552,555,2222,2225,2252,2255,
%T 2522,2525,2552,2555,5222,5225,5252,5255,5522,5525,5552,5555,22222,
%U 22225,22252,22255,22522,22525,22552,22555,25222,25225,25252,25255
%N Numbers using only the digits 2 and 5, or numbers that are both curved and linear.
%D M. J. Halm, Three Boxes, PuzzleM Magazine (Apr. 1987).
%H Vincenzo Librandi, <a href="/A072961/b072961.txt">Table of n, a(n) for n = 1..8190</a>
%t Flatten[Table[FromDigits/@Tuples[{2, 5}, n], {n, 5}]] (* _Vincenzo Librandi_, Aug 19 2016 *)
%o (Python)
%o from itertools import product
%o A072961_list = [int(''.join(a)) for l in range(1,11) for a in product('25',repeat=l)] # _Chai Wah Wu_, May 12 2016
%o (MAGMA) [n: n in [1..30000]  Set(Intseq(n)) subset {2,5}]; // _Vincenzo Librandi_, Aug 19 2016
%K easy,nonn,base
%O 1,1
%A _Michael Joseph Halm_, Aug 13 2002
