login
This site is supported by donations to The OEIS Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A169966 Numbers whose decimal expansion contains only 0's and 3's. 12
0, 3, 30, 33, 300, 303, 330, 333, 3000, 3003, 3030, 3033, 3300, 3303, 3330, 3333, 30000, 30003, 30030, 30033, 30300, 30303, 30330, 30333, 33000, 33003, 33030, 33033, 33300, 33303, 33330, 33333, 300000, 300003, 300030, 300033, 300300, 300303, 300330, 300333 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

FORMULA

a(n+1)=Sum_ k>=0 {A030308(n,k)*A093138(k+1)}. - From Philippe Deléham, Oct 16 2011.

a(n) = 3 * 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*3)))) \\ Charles R Greathouse IV, Nov 16 2011

(Haskell)

a169966 n = a169966_list !! (n-1)

a169966_list = map (* 3) a007088_list

-- Reinhard Zumkeller, Jan 10 2012

CROSSREFS

Cf. A007088, A014263, A169964, A169965, A169967.

Cf. A078242, A204093, A204094, A204095, A097256.

Sequence in context: A045863 A121023 A124520 * A140153 A095045 A061472

Adjacent sequences:  A169963 A169964 A169965 * A169967 A169968 A169969

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane, Aug 07 2010

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 17 19:58 EST 2019. Contains 319251 sequences. (Running on oeis4.)