%I #17 Apr 13 2021 23:01:47
%S 1,7,15,49,50,51,52,53,54,55,56,63,70,77,84,91,99,105,127,148,154,197,
%T 203,246,252,255,295,301,343,344,345,346,347,348,349,350,351,352,353,
%U 354,355,356,357,358,359,360,361,362,363,364
%N Positive numbers k such that every base-2 digit of k is a base-7 digit of k.
%H Reinhard Zumkeller, <a href="/A037376/b037376.txt">Table of n, a(n) for n = 1..10000</a>
%t mtchQ[n_]:=Module[{b7=Union[IntegerDigits[n,7]],b2=Union[IntegerDigits[n,2]]},MemberQ[Partition[b7,Length[b2],1],b2]]
%t Select[Range[400],mtchQ] (* _Harvey P. Dale_, Feb 20 2011 *)
%o (Haskell)
%o import Data.List ((\\), nub)
%o a037376 n = a037376_list !! (n-1)
%o a037376_list = filter f [1..] where
%o f x = null $ nub (ds 2 x) \\ nub (ds 7 x)
%o ds b x = if x > 0 then d : ds b x' else [] where (x', d) = divMod x b
%o -- _Reinhard Zumkeller_, May 30 2013
%Y Cf. A037372, A037373, A037374, A037375, A037377, A037378, A037379.
%K nonn,base
%O 1,2
%A _Clark Kimberling_