A037380 Numbers whose base-3 digits are all present among their base-4 digits.

1, 2, 4, 8, 13, 18, 22, 24, 25, 26, 28, 33, 36, 41, 56, 66, 70, 72, 73, 74, 75, 78, 81, 82, 84, 88, 96, 97, 98, 99, 100, 104, 108, 112, 114, 120, 121, 122, 129, 132, 133, 134, 135, 137, 141, 144, 145, 146, 147, 148, 149, 151, 152, 156, 157, 158, 161, 162, 164

Offset

1,2

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Maple

q:= n->  (f-> is({}=f(3) minus f(4)))({k-> convert(n, base, k)[]}):
select(q, [$1..200])[]; #  Alois P. Heinz, Jun 20 2021

Mathematica

Select[Range[200], SubsetQ[IntegerDigits[#, 4], IntegerDigits[#, 3]]&] (* Harvey P. Dale, Jan 19 2016 *)

Prog

(Haskell)
import Data.List ((\\), nub)
a037380 n = a037380_list !! (n-1)
a037380_list = filter f [1..] where
   f x = null $ nub (ds 3 x) \\ nub (ds 4 x)
   ds b x = if x > 0 then d : ds b x' else []  where (x', d) = divMod x b
-- Reinhard Zumkeller, May 30 2013

Crossrefs

Cf. A037381, A037382, A037383, A037384, A037385, A037386.

Sequence in context: A030058 A346992 A058329 * A328005 A186752 A360512

Adjacent sequences: A037377 A037378 A037379 * A037381 A037382 A037383

Keyword

nonn,base

Author

Clark Kimberling

Status

approved