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%I #10 Sep 24 2023 04:30:30
%S 1,2,3,4567,890,123,45678,901,23,4567890,1234,5,6,7,89012345,67,
%T 89012345678,90123,45678901,2345,678,901234,5678,9012345,67890,12345,
%U 678901,2345678,901234567,8901234567890,1234567,8901234567890123
%N Let S = 12345678901234567890123456..., the cyclic concatenation of digits; partition this string into distinct squarefree numbers. To avoid leading zeros, no member may end with the digit 9.
%e a(4) = 4567 because 4567 is squarefree, while 4, 45 and 456 are not.
%e a(5) = 890 because 89 would cause a(6) to have a leading 0.
%o (PARI) used = matrix(9, 60); x = 1; for (n = 1, 80, num = x; s = x; d = 1; while (used[s, d] || !issquarefree(num) || x == 9, x = (x + 1)%10; num = 10*num + x; d++); print1(num, ", "); used[s, d] = 1; x++); \\ _David Wasserman_, Feb 14 2005
%Y Cf. A085943.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Jul 14 2003
%E Corrected and extended by _David Wasserman_, Feb 14 2005