cp's OEIS Frontend

A037387 Numbers k such that every base-4 digit of k is a base-5 digit of k.

%I A037387 #16 Aug 04 2021 02:21:35
%S A037387 1,2,3,5,10,15,21,28,37,38,42,58,63,76,80,86,132,136,137,138,142,152,
%T A037387 160,167,178,183,190,191,202,204,205,210,213,214,215,217,220,221,222,
%U A037387 223,238,240,256,257,258,261,266,276,277,278
%N A037387 Numbers k such that every base-4 digit of k is a base-5 digit of k.
%H A037387 Reinhard Zumkeller, <a href="/A037387/b037387.txt">Table of n, a(n) for n = 1..10000</a>
%t A037387 Select[Range[300],SubsetQ[IntegerDigits[#,5],IntegerDigits[#,4]]&] (* _Harvey P. Dale_, Mar 27 2019 *)
%o A037387 (Haskell)
%o A037387 import Data.List ((\\), nub)
%o A037387 a037387 n = a037387_list !! (n-1)
%o A037387 a037387_list = filter f [1..] where
%o A037387    f x = null $ nub (ds 4 x) \\ nub (ds 5 x)
%o A037387    ds b x = if x > 0 then d : ds b x' else []  where (x', d) = divMod x b
%o A037387 -- _Reinhard Zumkeller_, May 30 2013
%Y A037387 Cf. A007090, A007091.
%Y A037387 Cf. A037388, A037389, A037390, A037391, A037392.
%K A037387 nonn,base
%O A037387 1,2
%A A037387 _Clark Kimberling_