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A169965 Numbers whose decimal expansion contains only 0's and 2's. 14
0, 2, 20, 22, 200, 202, 220, 222, 2000, 2002, 2020, 2022, 2200, 2202, 2220, 2222, 20000, 20002, 20020, 20022, 20200, 20202, 20220, 20222, 22000, 22002, 22020, 22022, 22200, 22202, 22220, 22222, 200000, 200002, 200020, 200022, 200200, 200202, 200220, 200222 (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)*A093136(k+1). - Philippe Deléham, Oct 16 2011

a(n) = 2 * 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*2)))) \\ Charles R Greathouse IV, Nov 16 2011

(Haskell)

a169965 n = a169965_list !! (n-1)

a169965_list = map (* 2) a007088_list

-- Reinhard Zumkeller, Jan 10 2012

CROSSREFS

Cf. A007088, A014263, A169964, A169966, A169967.

Cf. A078241, A204093, A204094, A204095, A097256.

Sequence in context: A112405 A136885 A136909 * A202170 A136908 A196748

Adjacent sequences:  A169962 A169963 A169964 * A169966 A169967 A169968

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane, Aug 07 2010

STATUS

approved

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Last modified February 23 01:58 EST 2020. Contains 332159 sequences. (Running on oeis4.)