A078243 -id:A078243 - cp's OEIS frontend

A169967 Numbers whose decimal expansion contains only 0's and 4's.

0, 4, 40, 44, 400, 404, 440, 444, 4000, 4004, 4040, 4044, 4400, 4404, 4440, 4444, 40000, 40004, 40040, 40044, 40400, 40404, 40440, 40444, 44000, 44004, 44040, 44044, 44400, 44404, 44440, 44444, 400000, 400004, 400040, 400044, 400400, 400404, 400440, 400444

Offset: 1

N. J. A. Sloane, Aug 07 2010

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Index entries for 10-automatic sequences.

Cf. A007088, A014263, A093141, A169964, A169965, A169966, A078243, A204093, A204094, A204095, A097256.

a169967 n = a169967_list !! (n-1)
a169967_list = map (* 4) a007088_list
-- Reinhard Zumkeller, Jan 10 2012

FromDigits/@Tuples[{0,4},6] (* Harvey P. Dale, Dec 21 2018 *)

print1(0);for(d=1,5,for(n=2^(d-1),2^d-1,print1(", ");forstep(i=d-1,0,-1,print1((n>>i)%2*4)))) \\ Charles R Greathouse IV, Nov 16 2011

a(n+1) = Sum_{k>=0} A030308(n,k)*A093141(k+1). - Philippe Deléham, Oct 16 2011

a(n) = 4 * A007088(n-1).

A096683 Least k such that decimal representation of k*n contains only digits 0 and 4.

Original entry on oeis.org

4, 2, 148, 1, 8, 74, 572, 5, 49382716, 4, 4, 37, 308, 286, 296, 25, 2612, 24691358, 2316, 2, 1924, 2, 19148, 185, 16, 154, 163127572, 143, 151876, 148, 14324, 125, 13468, 1306, 1144, 12345679, 12, 1158, 1036, 1, 1084, 962, 102428, 1, 98765432

Offset: 1

Ray Chandler, Jul 12 2004

Robert G. Wilson v, Table of n, a(n) for n = 1..10000

Cf. A004290, A078241-A078248, A079339, A096681, A096682, A096684, A096685, A096686, A096687, A096688.

f[n_] := Block[{id = {0, 4}, k = 1}, While[ Union[ Join[id, IntegerDigits[k*n]]] != id, k++]; k]; Array[f, 100] (* or *)
id = {0, 7}; lst = Union[ FromDigits /@ Flatten[ Table[ Tuples[id, j], {j, 15}], 1]]; If[ lst[[1]] == 0, lst = Rest@ lst]; f[n_] := (Min[ Select[lst, Mod[#, n] == 0 &]]/n) /. Infinity -> 0; Array[f, 100] (* or *)
id = {0, 7}; lst = Union[ FromDigits /@ Flatten[ Table[ Tuples[id, j], {j, 15}], 1]]; If[ lst[[1]] == 0, lst = Rest@ lst]; f[n_] := (SelectFirst[lst, Mod[#, n] == 0 &, 0]/n); a = Array[f, 100] (* requires Mathematica v10 *) (* Robert G. Wilson v, Sep 26 2016 *)

a(n) = A078243(n)/n.

cp's OEIS Frontend

A169967 Numbers whose decimal expansion contains only 0's and 4's.

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