A193493 - OEIS

A193493

Put the natural numbers together without spaces and read them five at a time advancing one space each time.

%I #14 Nov 21 2013 12:50:19

%S 12345,23456,34567,45678,56789,67891,78910,89101,91011,10111,1112,

%T 11121,11213,12131,21314,13141,31415,14151,41516,15161,51617,16171,

%U 61718,17181,71819,18192,81920,19202,92021,20212,2122,21222,12223,22232,22324,23242,32425

%N Put the natural numbers together without spaces and read them five at a time advancing one space each time.

%H Reinhard Zumkeller, <a href="/A193493/b193493.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = Sum (A007376(n+k)*10^(4-k): 0 <= k <= 4).

%t nn=40;With[{tbl=Flatten[IntegerDigits/@Range[nn]]},Table[FromDigits[ Take[tbl,{n,n+4}]],{n,nn}]](* _Harvey P. Dale_, Aug 10 2011 *)

%o (Haskell)

%o a193493 n = a193493_list !! (n-1)

%o a193493_list = f a007376_list where

%o f xs'@(x:xs) = ((foldl (\u v -> 10*u + v) 0) $ take 5 xs') : f xs

%Y Cf. A136414, A193431, A193492.

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Jul 28 2011