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A169964 Numbers whose decimal expansion contains only 0's and 5's. 14
0, 5, 50, 55, 500, 505, 550, 555, 5000, 5005, 5050, 5055, 5500, 5505, 5550, 5555, 50000, 50005, 50050, 50055, 50500, 50505, 50550, 50555, 55000, 55005, 55050, 55055, 55500, 55505, 55550, 55555, 500000, 500005, 500050, 500055, 500500, 500505, 500550, 500555 (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 sequences related to carryless arithmetic

FORMULA

a(n+1)=Sum_k>=0 {A030308(n,k)*A093143(k+1)}. - From Philippe Deléham, Oct 16 2011.

a(n) = 5 * 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*5)))) \\ Charles R Greathouse IV, Nov 16 2011

(Haskell)

a169964 n = a169964_list !! (n-1)

a169964_list = map (* 5) a007088_list

-- Reinhard Zumkeller, Jan 10 2012

CROSSREFS

Cf. A007088, A014263, A169965, A169966, A169967.

Cf. A078244, A204093, A204094, A204095, A097256.

Sequence in context: A136890 A136889 A136887 * A061474 A136916 A204193

Adjacent sequences:  A169961 A169962 A169963 * A169965 A169966 A169967

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane, Aug 07 2010

STATUS

approved

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Last modified October 23 01:24 EDT 2018. Contains 316518 sequences. (Running on oeis4.)