login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A045808 8-ish numbers (end in 67, 69, 81, 83). 2

%I #18 Nov 04 2013 12:19:17

%S 67,69,81,83,167,169,181,183,267,269,281,283,367,369,381,383,467,469,

%T 481,483,567,569,581,583,667,669,681,683,767,769,781,783,867,869,881,

%U 883,967,969,981,983,1067,1069,1081,1083,1167,1169,1181,1183,1267,1269

%N 8-ish numbers (end in 67, 69, 81, 83).

%H Reinhard Zumkeller, <a href="/A045808/b045808.txt">Table of n, a(n) for n = 1..1000</a>

%F Empirical G.f.: x*(67+2*x+12*x^2+2*x^3+17*x^4)/(1-x-x^4+x^5). [Colin Barker, Jan 23 2012]

%t Select[Range[1300],MemberQ[{67,69,81,83},Mod[#,100]]&] (* _Harvey P. Dale_, Jul 03 2013 *)

%o (Haskell)

%o import Data.List (findIndices)

%o a045808 n = a045808_list !! (n-1)

%o a045808_list = findIndices (`elem` [67,69,81,83]) $ cycle [0..99]

%o -- _Reinhard Zumkeller_, Jan 23 2012

%Y Cf. A045800-A045809.

%Y Cf. A045572, A045797, A045798.

%K nonn,base,easy

%O 1,1

%A _J. H. Conway_.

%E More terms from _Erich Friedman_.

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 04:13 EDT 2024. Contains 371235 sequences. (Running on oeis4.)