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A193493
Put the natural numbers together without spaces and read them five at a time advancing one space each time.
5
12345, 23456, 34567, 45678, 56789, 67891, 78910, 89101, 91011, 10111, 1112, 11121, 11213, 12131, 21314, 13141, 31415, 14151, 41516, 15161, 51617, 16171, 61718, 17181, 71819, 18192, 81920, 19202, 92021, 20212, 2122, 21222, 12223, 22232, 22324, 23242, 32425
OFFSET
1,1
LINKS
FORMULA
a(n) = Sum (A007376(n+k)*10^(4-k): 0 <= k <= 4).
MATHEMATICA
nn=40; With[{tbl=Flatten[IntegerDigits/@Range[nn]]}, Table[FromDigits[ Take[tbl, {n, n+4}]], {n, nn}]](* Harvey P. Dale, Aug 10 2011 *)
PROG
(Haskell)
a193493 n = a193493_list !! (n-1)
a193493_list = f a007376_list where
f xs'@(x:xs) = ((foldl (\u v -> 10*u + v) 0) $ take 5 xs') : f xs
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jul 28 2011
STATUS
approved