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A169967 Numbers whose decimal expansion contains only 0's and 4's. 14
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

Index entries for 10-automatic sequences.

FORMULA

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

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

PROG

(PARI) 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

(Haskell)

a169967 n = a169967_list !! (n-1)

a169967_list = map (* 4) a007088_list

-- Reinhard Zumkeller, Jan 10 2012

CROSSREFS

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

Sequence in context: A104292 A131535 A077329 * A061473 A091104 A069539

Adjacent sequences:  A169964 A169965 A169966 * A169968 A169969 A169970

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane, Aug 07 2010

STATUS

approved

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Last modified February 18 23:26 EST 2018. Contains 299330 sequences. (Running on oeis4.)