login
A085943
Let S = 123456789101112131415..., the concatenation of the natural numbers; partition this string into distinct squarefree numbers. To avoid leading zeros, no number may end at the digit that comes before a 0 in S.
1
1, 2, 3, 4567, 89, 10, 11, 1213, 14, 15, 161, 7, 181, 9202, 122, 23, 242526, 27282, 930, 31, 323, 33, 43, 5, 3637, 38, 39, 404142, 434, 445, 46, 47, 4849, 505, 15253, 545, 55, 6, 57, 58, 59, 606, 1626, 3646, 566, 67, 6869, 70, 71, 727, 37, 4757, 677, 78, 79, 8081, 82
OFFSET
0,2
EXAMPLE
a(18) = 27282 because 27282 is squarefree, while 27, 272 and 2728 are not and 2 has already been used.
a(19) = 930 because 9 is not squarefree and 93 would cause a(20) to have a leading 0.
CROSSREFS
Sequence in context: A097301 A020345 A341715 * A068661 A271631 A068826
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Jul 14 2003
EXTENSIONS
More terms from David Wasserman, Feb 14 2005
STATUS
approved