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A077309
Concatenation of n numbers starting with n.
2
1, 23, 345, 4567, 56789, 67891011, 78910111213, 89101112131415, 91011121314151617, 10111213141516171819, 1112131415161718192021, 121314151617181920212223
OFFSET
1,2
LINKS
MATHEMATICA
Table[FromDigits@ Flatten@ Take[#, {n, n + (n - 1)}], {n, Ceiling[Length[#]/2]}] &@ Array[IntegerDigits, 23] (* Michael De Vlieger, May 13 2017 *)
CROSSREFS
Sequence in context: A025993 A111875 A028035 * A042016 A025976 A025989
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Nov 03 2002
EXTENSIONS
a(7) corrected by Michael De Vlieger, May 13 2017
STATUS
approved