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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A030143 Even numbers in which parity of digits alternates. 7
0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 30, 32, 34, 36, 38, 50, 52, 54, 56, 58, 70, 72, 74, 76, 78, 90, 92, 94, 96, 98, 210, 212, 214, 216, 218, 230, 232, 234, 236, 238, 250, 252, 254, 256, 258, 270, 272, 274, 276, 278, 290, 292, 294, 296, 298, 410, 412, 414 (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

(1 - a(n) mod 2) * A228710(a(n)) = 1. - Reinhard Zumkeller, Aug 31 2013

MATHEMATICA

id[n_]:=IntegerDigits[n]; t={}; Do[If[Length[id[n]]==1, AppendTo[t, n], If[Union[Abs[Differences[Boole /@ EvenQ[id[n]]]]]=={1}, AppendTo[t, n]]], {n, 0, 414, 2}]; t (* Jayanta Basu, May 07 2013 *)

PROG

(Haskell)

a030143 n = a030143_list !! (n-1)

a030143_list = filter even a030141_list

-- Reinhard Zumkeller, Aug 31 2013

CROSSREFS

Cf. A030142, A062285, intersection of A005843 and A030141.

Sequence in context: A152966 A066122 A119766 * A110725 A100800 A169921

Adjacent sequences:  A030140 A030141 A030142 * A030144 A030145 A030146

KEYWORD

nonn,base,easy

AUTHOR

Patrick De Geest

EXTENSIONS

Offset corrected by Reinhard Zumkeller, Aug 31 2013

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 19 12:07 EDT 2018. Contains 316360 sequences. (Running on oeis4.)